Tissue surface ablation temperature identification system and monitoring method based on real-time image feedback

Abstract

The present application relates to a kind of tissue surface ablation temperature identification system and temperature monitoring method based on real-time image feedback, the system includes the model of the color and temperature correspondence of tumor target tissue surface image being configured with ablation device, for real-time acquisition of the surface image of tumor target tissue Image acquisition device and for the matching of image color and temperature, temperature identification device;Real-time temperature value of tumor target tissue surface is monitored by the system.The present application establishes the model of tumor target tissue surface image and temperature data correspondence, the image of tumor tissue surface is continuously photographed in ablation process, and the temperature change of tumor surface in ablation process is displayed in real time after the processing of computer, can provide accurate reference to the selection of ablation parameter of doctor in microwave ablation operation process.

Description

TECHNICAL FIELD

[0001] The present application relates to a tissue surface ablation temperature identification system and monitoring method based on real-time image feedback, belonging to the field of ablation technology. BACKGROUND

[0002] In recent years, ablation technology has been widely used in the treatment of various solid tumors, especially in the treatment of liver cancer and lung cancer. During microwave ablation, doctors usually cannot directly monitor the temperature changes of the ablation tissue and its surrounding organs. Generally, CT images are taken at stages during the ablation process, and then the doctor judges the current ablation result according to his own experience. In order to ensure that the ablation result meets the expectations, the number of CT images taken is usually increased to improve the accuracy of the judgment, thus increasing the risk of exposure of the patient to radiation, increasing the economic burden of the patient, and increasing the complexity of the surgical procedure for the doctor. Moreover, CT images have a lag relative to the actual ablation result, and cannot monitor the ablation result in real time.

[0003] The prior art estimates the ablation effect in the operation through the preoperative simulated ablation image. Since the simulation effect is usually calculated through ex vivo data and experience data, there is a lack of correction of real-time data during the operation, so there is usually a large difference between the simulated ablation image and the actual ablation effect, and the clinical value is difficult to reflect.

[0004] Due to the above reasons, there is no effective means to continuously monitor the entire ablation process during the operation. SUMMARY

[0005] The technical problem to be solved by the present application is to establish a correspondence between the ablation tissue surface image and the temperature, so as to assist the doctor in accurately identifying and monitoring the temperature change of the ablation tissue surface during the operation, and then adjusting the ablation parameters to prevent damage to other normal tissues during the ablation operation.

[0006] In order to solve the above technical problems, on the one hand, the present application provides a tissue surface ablation temperature identification system based on real-time image feedback, comprising:

[0007] an ablation device configured with a model of the color and temperature correspondence of the tumor target tissue surface image, referred to as a first relationship model;

[0008] an image acquisition device for real-time acquisition of the surface image of the tumor target tissue, referred to as a first image;

[0009] a temperature identification device for matching the color of each pixel of the first image with the first relationship model to obtain the real-time temperature value of the tumor target tissue surface.

[0010] In another aspect, the present application also provides a tumor surface ablation temperature monitoring method based on real-time image feedback, which adopts the above-mentioned tumor surface ablation temperature identification system and comprises the following steps:

[0011] The image acquisition device acquires a first image in real time;

[0012] The temperature identification device finds the temperature value corresponding to the color of each pixel of the first image from the first relationship model, that is, obtains the real-time temperature value of the tumor target tissue surface.

[0013] The present application can real-time display and monitor the temperature change of the tumor surface in the ablation process by establishing a tumor target tissue surface image and temperature data corresponding relationship model database, continuously shooting the image of the tumor tissue surface as a first image in the ablation process, and finding the temperature value corresponding to the color of each pixel of the first image from the first relationship model. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a structure schematic diagram of an ablation needle in the present application.

[0015] Figure 2 is a structure schematic diagram of an ablation needle in the present application. Figure 1 is a cross-sectional schematic diagram of the inner rod in the present application.

[0016] The reference signs are as follows: 1, ablation needle; 2, needle rod body; 3, sleeve; 4, channel. DETAILED DESCRIPTION

[0017] In clinical treatment, the ablation operation lacks a suitable real-time monitoring means, resulting in an uncontrollable ablation process, and thus an intermittent ablation is needed to ensure the safety and reliability of the ablation process and to ensure that the ablation is not excessive. In the tumor ablation operation process, in order to monitor the temperature change of the tumor target tissue in the ablation process, the doctor generally adopts a side temperature measurement, or some designs a temperature measurement point on the ablation needle, but the above-mentioned two temperature measurement methods cannot real-time reflect the local temperature change of the tumor target tissue. The temperature measurement point designed on some ablation needles can only measure the temperature of the cooling water and cannot measure the temperature change of the tumor. In addition, in the prior art, the temperature change of the tumor cannot be displayed on the ablation system in time and accurately, and the denaturation trend of the whole tumor cannot be observed. The technical scheme of the present application can directly observe the local temperature change of the tumor in the ablation process.

[0018] The technical scheme of the present application will be further described in detail in combination with the embodiments and the drawings, but the embodiments of the present application are not limited thereto.

[0019] Embodiment one: the embodiment provides a tissue surface ablation temperature identification system based on real-time image feedback, comprising:

[0020] An ablation device configured with a model of color and temperature correspondence of a tumor target tissue surface image, referred to as a first relationship model;

[0021] An image acquisition device for acquiring a tumor target tissue surface image in real time, referred to as a first image;

[0022] A temperature identification device for matching the color of each pixel of the first image with the first relationship model to obtain a real-time temperature value of the tumor target tissue surface.

[0023] The tumor target tissue surface image as the first image can be collected through a natural cavity or collected using an artificial cavity. Taking the collection using an artificial cavity as an example, the ablation device includes an ablation needle, such as Figure 1 As shown, the ablation needle includes a needle shaft body and a sleeve provided on the needle shaft body, and the sleeve is provided with a passage for the free passage of a shooting element of an image acquisition device. The image acquisition device in the embodiment is preferably an endoscope. When the ablation needle 1 is inserted into the tumor target tissue for ablation, the endoscope is inserted into the passage 4 to collect the color change of the tumor target tissue surface, which corresponds to the first relationship model previously stored in the ablation system, so as to display the temperature change of the tumor target tissue surface in real time. In some cases, the endoscope can also be used to shoot the tumor target tissue surface through a natural cavity to obtain the first image.

[0024] In order to accurately know the specific position of the collected first image on the entire tumor target tissue, the application also uses CT, MRI and other image acquisition devices to collect image data of the tumor, and simulates a three-dimensional model of the tumor target tissue in the ablation system. And register the first image and the three-dimensional model of the tumor target tissue, reflect the real-time temperature value of the tumor target tissue surface on the three-dimensional model, which can directly display the temperature change of the tumor target tissue surface at the first image.

[0025] Since the ablation shape of the ablation needle is an ellipsoid or a sphere, and before the operation planning, some data of the ablation needle previously stored need to be input, including the ablation needle model, the needle shaft diameter, the effective length, the position of the ablation center, and the ablation power, time and ablation range data information. The first image on the three-dimensional model of the tumor target tissue and the information of the ablation center can be used to simulate a temperature change model matched with the ablation shape.

[0026] The first relationship model is obtained by experimental method in this embodiment. In order to be rigorous and reduce errors in the experiment, the equipment used in the experiment will be consistent with the equipment used in the operation process. 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, reduce color difference, and simulate the surgical environment of human tissue.

[0027] The steps of the experimental method are as follows:

[0028] Firstly, the ex vivo tissue is placed in a light-tight box to simulate the ablation environment of human liver tissue, so that the subsequent endoscopic shooting results are consistent with the actual ablation process. A plurality of temperature measuring points are arranged on the surface of the ex vivo tissue, and a thermocouple is arranged on each temperature measuring point to measure the temperature of the temperature measuring point.

[0029] In this embodiment, the ex vivo tissue is a pig liver ex vivo for 4 hours. The pig liver is stored in an electric heating constant temperature water tank before ablation, so that the temperature of the liver tissue is maintained at 36.5±2℃.

[0030] Secondly, the ablation needle is inserted into the ex vivo tissue through the box to simulate the ablation process of the ex vivo tissue. It should be noted that in order to collect the temperature change image information of 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, as described in Figure 1 and 2 The existing ablation needle 1 is improved in this embodiment. A sleeve 3 is installed on the needle shaft body 2, and a channel 4 for the endoscope to freely enter and exit is formed 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 process. The above-mentioned setting in this embodiment is also used to simulate this shooting process. After adjusting the angle of the endoscope lens and the distance between the endoscope lens and the needle tip, the endoscope is fixed in place. At this time, the image of the tissue surface can be shot.

[0031] The endoscope in this embodiment adopts the Guantai series submillimeter ultrafine optical fiber endoscope, which has optical fiber image transmission and light guide functions. The probe has good flexibility, smaller diameter, and can detect through bending and narrow channels. It can be directly observed through the ocular lens, or connected with the display screen through the USB OTG interface to shoot and process images, which is simple to operate. The field of view of the endoscope is 70°-120°, the one-way bending angle of the probe is ≥150°, the depth of field is 5-50mm, and it has the function of optical fiber light guide, which is convenient for illumination.

[0032] It should be noted that due to the limitations of the field of view, bending angle and depth of field of the endoscope, if the endoscope and the ablation needle are fixed as a whole, the image collected by the endoscope will be unclear during the movement of the ablation needle, or part or all of the tumor target area will move out of the endoscope lens during the movement, which cannot be accurately punctured.

[0033] Third step, extend the endoscope from the channel 4, adjust the lens angle of the endoscope and the distance between the endoscope lens and the needle tip, so that the image of the visible range of the surface of the ex vivo tissue can be taken.

[0034] Fourth step, set the ablation parameters of the ablation needle, and ablate the ex vivo tissue. During the ablation process, take pictures of the ex vivo tissue to obtain a plurality of first images. According to the RGB value of each pixel in the first image, the corresponding relationship between the surface temperature value of the ex vivo tissue and the RGB value is obtained, which is referred to as the first relationship model.

[0035] The process of obtaining the first relationship model can be summarized as follows: the ablation device ablates the ex vivo tissue, a plurality of temperature measurement points are set on the ex vivo tissue, the first image during the ablation process of the ex vivo tissue is continuously collected, and the temperature value of the temperature measurement point is obtained. The relationship between each temperature measurement point and the RGB color value of the pixel corresponding to the temperature measurement point in the first image is obtained, thereby establishing the first relationship model.

[0036] During the actual ablation operation, the doctor obtains the real-time temperature value of the tissue surface based on the first relationship model through the real-time image of the tissue surface. That is, through the endoscope matched with the ablation needle, the real-time image of the tissue surface is obtained, and the real-time temperature value of the tissue surface is obtained by inversely deducing 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. On the premise of ensuring the ablation effect, prevent other normal tissues from being damaged during the ablation operation.

[0037] Since the RGB value of each pixel in the first image contains three channel data, 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 further obtain a corresponding relationship model between each temperature measurement point of the ex vivo tissue and the gray value of the corresponding pixel in the second image, which is referred to as the second relationship model. The real-time temperature value corresponding to the tissue surface is obtained based on the second relationship model through the gray image of the real-time image of the tissue surface.

[0038] There are many methods for converting the RGB value of the first image to the gray value, which are all 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:

[0039] Gray=(R*19595+G*38469+B*7472)>>16,

[0040] In the formula, 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.

[0041] It should be noted that the first relationship model in the application can be continuously optimized and corrected according to the temperature values measured during the actual ablation operation and the collected image information, so as to obtain a more accurate database.

[0042] Embodiment two: the embodiment proposes a tissue surface ablation temperature monitoring method based on real-time image feedback, which is applied to the tissue surface ablation temperature identification system based on real-time image feedback in embodiment one, and the method comprises the following steps:

[0043] Collect image information of the tumor target tissue by using CT, MRI and other image collection devices, determine the specific position of the target tissue, and do related work such as operation planning;

[0044] Insert the ablation needle into the tumor target tissue;

[0045] The image collection device adopts an endoscope, as shown in Figure 1 and Figure 2 The endoscope is inserted into the body through the channel 4 reserved on the ablation needle, so that the endoscope can clearly collect the image information of the tumor target tissue surface;

[0046] Set the ablation parameters of the ablation needle and start ablation;

[0047] Collect the first image in real time through the endoscope;

[0048] The temperature identification device finds the temperature value corresponding to the color of each pixel of the first image from the first relationship model, that is, obtains the real-time temperature value of the tumor target tissue surface, and displays it on the display interface of the ablation device.

[0049] The temperature identification device finds the temperature value corresponding to the color of each pixel of the first image from the first relationship model, that is, obtains the real-time temperature value of the tumor target tissue surface.

[0050] The embodiment can also be improved as follows: the ablation device generates a three-dimensional model of the tumor target tissue, registers the first image and the three-dimensional model, makes the real-time temperature value of the tumor target tissue surface reflected on the three-dimensional model, and thus obtains the real-time temperature field of the tumor target tissue surface.

[0051] The real-time information of the first image is continuously collected, and the first relationship model database pre-stored by the ablation system is used to obtain the real-time temperature change information on the three-dimensional model.

[0052] In the embodiment, the first relationship model is obtained by using the experimental method in embodiment one, and the first relationship model is obtained according to the RGB value of each pixel in the first image and the measured temperature value.

[0053] In the embodiment, the second relationship model library is obtained by the method in embodiment one, the first image is subjected to gray scale processing to obtain a second image, and a corresponding relationship between each temperature measurement point of the ex vivo tissue and a gray scale value of a corresponding pixel of the second image is further obtained.

[0054] The technical solutions in the embodiments one and two can be used in microwave, radio frequency, ultrasonic and other ablation operations.

[0055] It should be noted that the above description of the present application and its embodiments is illustrative and not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the present application. Therefore, if a person skilled in the art is inspired by it, without departing from the purpose of the present application, similar methods and embodiments can be designed without creativity, which should belong to the protection scope of the present application.

Claims

1. A tissue surface ablation temperature recognition system based on real-time image feedback, characterized in that: include: The ablation device is configured with a model of the corresponding relationship between the color and temperature of the tumor target tissue surface image, referred to as the first relationship model; An image acquisition device, used for acquiring a surface image of the tumor target tissue in real time, referred to as a first image; a temperature recognition device, configured to match the color of each pixel of the first image with the first relationship model to obtain a real-time temperature value of the surface of the tumor target tissue; The ablation device includes an ablation needle, which includes a needle shaft body and a sleeve arranged on the needle shaft body, wherein the sleeve is provided with a channel for a shooting element of an image acquisition device to freely pass through; The first relationship model is obtained by the following method: The ablation device ablates the ex vivo tissue, sets multiple temperature measuring points on the ex vivo tissue, continuously collects a first image during 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 a first relationship model.

2. The tissue surface ablation temperature recognition system based on real-time image feedback according to claim 1, characterized in that: The shooting element of the image acquisition device is a shooting element that can pass through a natural cavity.

3. The tissue surface ablation temperature recognition system based on real-time image feedback according to claim 1, characterized in that: The ablation device is used to generate a three-dimensional model of the tumor target tissue, align the first image with the three-dimensional model, and reflect the obtained real-time temperature value of the surface of the tumor target tissue on the three-dimensional model.

4. The tissue surface ablation temperature recognition system based on real-time image feedback according to claim 1, characterized in that: The first image is grayscaled to obtain a second image, and the correspondence between each temperature measurement point of the ex vivo tissue and the grayscale value of the corresponding pixel in the second image is further obtained, which is referred to as the second relationship model. Based on the second relationship model, the real-time temperature value of the tumor target tissue surface is obtained through the grayscale image of the real-time image of the tumor target tissue surface.

5. The tissue surface ablation temperature recognition system based on real-time image feedback according to claim 4, characterized in that: The corresponding relationship between the RGB value of each pixel in the first image and the grayscale value of the corresponding pixel in the second image is: Gray=(R*19595+G*38469+B*7472)>>16; Where Gray is the grayscale 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.

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