CN100459950C - Image-guided water-cooled radiofrequency ablation tumor treatment all-in-one machine - Google Patents

Abstract

The invention relates to an image-guided water-cooled radio frequency ablation tumor treatment integrated machine, which consists of a circulating water cooling device, a controllable radio frequency power source, a three-dimensional positioning system, a water-cooled needle-shaped ablation electrode, an ultrasonic imaging probe, a B-type ultrasonic imaging system, Composed of computer network system, intelligent monitoring software, treatment planning software and man-machine dialogue peripherals, it organically integrates radiofrequency ablation technology and ultrasound imaging technology, and combines computer-assisted surgery system to establish a position parameter and The three-dimensional model of color parameters such as color value, hue, and saturation can be visualized; during the operation, control the radio frequency power and cooling water temperature according to the established treatment plan, collect images of the patient's target tissue in real time, and dynamically determine the ablation status of the lesion , and adjust the working parameters of the controllable radio frequency power source accordingly, so that the ablation treatment is in the best state; after the operation, the image of the target tissue of the patient is collected again, and the final evaluation of the treatment effect is carried out.

Description

Image-guided water-cooled radiofrequency ablation tumor treatment all-in-one machine

technical field

The invention relates to an image-guided water-cooled radiofrequency ablation and tumor treatment all-in-one machine, which organically integrates radiofrequency ablation technology and ultrasonic imaging technology. Ultrasound images are not only used to locate the target tissue, but also to track the changes in the tissue characteristics of the target tissue, and based on this, the whole process of radiofrequency ablation in situ inactivation process can be monitored to ensure the safety and effectiveness of ablation treatment. The invention is applied to tumor treatment and belongs to the technical field of biomedical engineering.

Background technique

The radiofrequency tumor ablation treatment system based on radiofrequency in situ inactivation technology has become a popular tumor treatment method because of its wide indications, minimal trauma, good curative effect, fast safety, and convenience. At present, there are about 10 kinds of products at home and abroad, and they can be roughly divided into two types: cold cycle type and "multi-warhead" type. However, all products have a fatal shortcoming, that is, they do not track the changes in the tissue characteristics of the target tissue, and implement the whole process of radiofrequency ablation in situ inactivation process monitoring accordingly, so as to complete the treatment safely and effectively. Instead, it is judged whether the ablation treatment is completed by timing or according to the impedance change of the target tissue. It is often either insufficient ablation or excessive ablation. the health of the patient. Recently, some doctors have also begun to use B-ultrasound to monitor the in situ inactivation process of radiofrequency ablation, and then judge whether the ablation treatment is completed based on experience. Although this has greatly improved the treatment process, there are still shortcomings such as lack of scientific consideration and difficult operation.

During the in situ inactivation process of radiofrequency ablation, the tumor cells in the target tissue undergo thermal coagulation due to temperature rise, forming necrosis, and the scope continues to expand until it covers the entire lesion. During the coagulation and necrosis process of the above-mentioned lesion, the B-ultrasound image of the lesion will have obvious changes, and the color value, hue, and saturation data of each pixel will change accordingly. Because of this, not only the in-situ inactivation process of radiofrequency ablation can be observed, but also the whole process can be monitored. This is the basic principle of the image-guided water-cooled radiofrequency ablation tumor treatment all-in-one machine. At the same time, with the rapid development of computer technology and medical imaging technology, the computer integrated surgery system has made great progress, which also provides a technical basis for the development of image-guided water-cooled radiofrequency ablation and tumor treatment all-in-one machine.

According to the literature search, there is no report about image-guided radiofrequency ablation tumor treatment machine. No patents related to image-guided radiofrequency ablation technology were found after searching "China Patent", "Hong Kong Intellectual Property Office Online Search System", and "US Patent and Trademark Office Online Patent Search". The feature of the US patent "RFablation system and method having automatic temperature control" (inventor Sherman et al., patent number: 6,558,378) is that the temperature of the ablation area is automatically controlled to It prevents the target tissue from gasification and carbonization due to excessive temperature, so as to obtain a larger ablation zone, but its effect is not as good as that of the cold cycle needle ablation electrode. This patent does not involve tracking the changes in the tissue characteristics of the target tissue, and monitoring the whole process of radiofrequency ablation in situ inactivation, etc., and there are obvious deficiencies.

Contents of the invention

The purpose of the present invention is to provide an image-guided water-cooled radiofrequency ablation tumor treatment all-in-one machine for the deficiencies of the prior art and the needs of clinical applications, which has the characteristics of excellent performance, safe use, significant curative effect, scientific and standardized operation, etc., to benefit patients .

In order to achieve such a purpose, the technical solution of the present invention applies radiofrequency ablation technology, medical imaging technology, water cooling technology and intelligent control technology, and organically integrates them to form a computer-integrated surgical system.

The image-guided water-cooled radio frequency ablation tumor treatment all-in-one machine designed by the present invention includes: a circulating water cooling device, a controllable radio frequency power source, a three-dimensional positioning system, a water-cooled needle-shaped ablation electrode, an ultrasonic imaging probe, a B-type ultrasonic imaging system, and a computer Network system, intelligent monitoring software, treatment planning software and man-machine dialogue peripherals.

The circulating water cooling device is connected with the computer network system through the connection cable, and communicated with the water-cooled needle-shaped ablation electrode through the water inlet and outlet pipes. The controllable radio frequency power source is respectively connected with the water-cooled needle-shaped ablation electrode and the computer network system through connecting cables. The water-cooled needle-shaped ablation electrode is installed on the No. 1 movable arm of the three-dimensional positioning system, and can be inserted into the target tissue of the patient during treatment. The ultrasonic imaging probe is installed on the No. 2 movable arm of the three-dimensional positioning system, which can be in contact with the body surface above the patient's target tissue during treatment, and is connected to the B-type ultrasonic imaging system through a connecting cable. The B-type ultrasonic imaging system is connected with the computer network system through a connecting cable. The three-dimensional positioning system is a complex electromechanical system controlled by the computer network system, which is connected to the computer network system through connecting cables; the man-machine dialogue peripherals include keyboards, mice, etc., which are connected to the computer network system through their own connecting cables; Intelligent monitoring software and treatment planning software are installed in the memory of the computer network system; the computer network system is connected to the circulating water cooling device, controllable radio frequency power source, three-dimensional positioning system, and B-type ultrasonic imaging system through connecting cables; the computer network The system can also read preoperative CT image data and preoperative MR image data respectively through the network connection cable.

The circulating water cooling device can adopt existing equipment (refer to the published invention patent CN1593353, "Water-cooled radio frequency tumor ablation treatment system". The return water pipe and the water outlet pipe are respectively connected with the water-cooled needle-shaped ablation electrode, and the control signal Both the wire and the temperature sensor are connected to the computer network system through connecting cables.

The controllable radio frequency power source can adopt the existing circuit (refer to the published invention patent CN1593353, "Water-cooled radio frequency tumor ablation treatment system"). A PWM (Pulse Width Modulation) signal from a computer network system is applied to its control input, and its output outputs controlled RF power accordingly.

The water-cooled needle-shaped ablation electrode adopts an existing device (see the authorized invention patent ZL200310122792.1 "Single-needle water-cooled radiofrequency ablation electrode"). The connecting cable is connected with the main box through the cable plug, the radio frequency energy is input from the controllable radio frequency power source, and the temperature detection signal is output to the computer network system; the water inlet and outlet pipes are connected to the circulating water cooling device. The water-cooled needle-shaped ablation electrode is inserted into the target tissue, and the guide electrode is closely attached to the patient's buttocks or outer thighs. The two form a radio frequency circuit to perform radio frequency capacitive heating on the lesion.

The three-dimensional positioning system is a complex electromechanical system controlled by a computer network system, consisting of a bracket, a three-dimensional movement arm, a No. 1 movable arm, a No. 2 movable arm and an electromagnetic tracking module. The bracket is fixedly installed on the ground. The electromagnetic tracking module is installed on the bracket, and the electromagnetic tracking module is connected with the computer network system and the three-dimensional movement arm through the connecting cable, and is used to track the positions of the ultrasonic imaging probe, the water-cooled needle-shaped ablation electrode and the human body to ensure that the coordinates of the three are unified. The three-dimensional motion arm is connected to the bracket, and can move up and down, left and right, and forward and backward, so that the water-cooled needle-shaped ablation electrode and the ultrasonic imaging probe can quickly approach the target tissue. The No. 1 movable arm is connected to the three-dimensional movement arm, which can perform precise three-dimensional movement, and the position error generated during the movement is not more than 1mm. The water-cooled needle-shaped ablation electrode is detachably installed on the No. 1 movable arm, and can be accurately inserted into the lesion by the movement of the No. 1 movable arm. The No. 2 movable arm is also connected to the three-dimensional movement arm. In addition to making precise three-dimensional movements to make the ultrasound imaging probe accurately face the target tissue, it can also move in parallel so that the ultrasound imaging probe can obtain a series of images of the target tissue for supply Reconstruct the 3D image using . The three-dimensional positioning system provides sufficient degrees of freedom, and all dimensional movements are controlled by the computer network system.

The ultrasonic imaging probe and B-type ultrasonic imaging system are mature products, which directly transmit the acquired image information to the computer network system.

The hardware platform of the computer network system takes high-end microcomputer as the core, and is equipped with plug-in cards such as image acquisition card, multi-function data acquisition card, control card, Internet interface, PCI and ISA bus, USB interface, and stored in the memory. Monitoring software, treatment planning software, operating system is Windows XP.

The programming language of the intelligent monitoring software and treatment planning software is C ₊₊ .

The man-machine dialogue peripherals include a keyboard and a mouse, which are used to realize the interactive operation between the user and the computer, that is, manual intervention can be performed through the man-machine dialogue peripherals.

Computer network system, man-machine dialogue peripherals, intelligent monitoring software and treatment planning software constitute a complete computer-assisted surgery system.

Before the operation, the patient's lesion, that is, the target tissue, is firstly positioned through the ultrasound imaging probe and the B-mode ultrasound imaging system installed on the No. 2 movable arm of the three-dimensional positioning system. After determining the position of the target tissue, further obtain the sequential tomographic images of the patient's target tissue, and then through image segmentation, extraction of isosurface and other processing, establish a 3D model and visualize it, and at the same time distinguish the structures of interest such as lesions, blood vessels, bones, etc. Ablation range. The three-dimensional model, that is, the position parameters x, y, z of each pixel in the reconstructed three-dimensional image, and the data of color parameters such as color value, hue, saturation, etc. are transmitted to the computer network system and stored, and it is used as the benchmark of the target tissue Model. Based on this, a treatment plan can be formulated: determine the needle insertion position, radiofrequency dose, cooling water temperature, etc. of the water-cooled radiofrequency ablation electrode needle. In addition, in order to achieve the connection and unification between the patient's body coordinates and the image coordinates, it is necessary to set ultrasound-sensitive marks on the surface of the human body. In order to achieve more precise treatment, the target tissue image can also be acquired by the CT imaging system or MR imaging system before operation, and the preoperative CT image data and preoperative MR image data can be fused with ultrasound images for multimodal information.

During the operation, the three-dimensional positioning system is adjusted according to the established treatment plan, and the water-cooled radiofrequency ablation electrode needle is inserted into the target tissue under the guidance of the ultrasound image. Then start the controllable radio frequency power source and the circulating water cooling device, the former outputs the radio frequency power according to the formulated treatment plan, that is, the radio frequency dose, and the latter keeps the temperature of the cooling water at the set value. At the same time, the image of the patient's target tissue is collected through the ultrasonic imaging probe and the B-mode ultrasonic imaging system, and is registered with the 3D model established before the operation, and the color parameters such as the color value, hue, and saturation of each pixel are reflected in real time, accurately, and dynamically. Changes, and then determine the ablation status of the lesion, and issue corresponding instructions to adjust the working parameters of the controllable RF power source, that is, to change the amplitude and working ratio of the RF output, so that the ablation treatment is in the best state. Such continuous acquisition, adjustment, re-acquisition, and re-adjustment means that the patient model and operation plan are continuously updated in time until the new target tissue model is consistent with the target tissue model set in the treatment plan when the treatment is completed. After the ablation treatment is completed, the all-in-one machine automatically terminates the treatment.

After surgery, images of the patient's target tissue are reacquired for a final assessment of treatment effectiveness.

The present invention organically integrates the radio frequency ablation technology and the ultrasonic imaging technology. The ultrasonic image is no longer only used to locate the target tissue, but also to track the change of the tissue characteristics of the target tissue, and implement the in situ inactivation process of the radio frequency ablation accordingly. Full-process monitoring to ensure the safety and effectiveness of ablation therapy. The invention is suitable for clinical treatment of diseases such as liver cancer, lung cancer, kidney cancer and prostate cancer, and has broad application prospects and market potential.

Description of drawings

Fig. 1 is a schematic diagram of the composition and structure of the system of the present invention.

In Fig. 1, 1 is a circulating water cooling device, 2 is a controllable radio frequency power source, 3 is a three-dimensional positioning system, 4 is a water-cooled needle ablation electrode, 5 is an ultrasound imaging probe, 6 is a B-type ultrasound imaging system, and 7 is a Computer network system, 8 is intelligent monitoring software, 9 is treatment planning software, 10 is man-machine dialogue peripherals.

Fig. 2 is a schematic diagram of the three-dimensional positioning system of the present invention.

In Fig. 2, 11 is a bracket, 12 is a three-dimensional motion arm, 13 is a No. 1 movable arm, 14 is a No. 2 movable arm, and 15 is an electromagnetic tracking module.

Detailed ways

In order to better understand the technical solution of the present invention, a further detailed description will be made below in conjunction with the accompanying drawings.

The composition structure of the system of the present invention is shown in FIG. 1 . It includes circulating water cooling device 1, controllable radio frequency power source 2, three-dimensional positioning system 3, water-cooled needle ablation electrode 4, ultrasonic imaging probe 5, B-type ultrasonic imaging system 6, computer network system 7, intelligent monitoring software 8 , treatment planning software 9 and man-machine dialogue peripherals 10.

The circulating water cooling device 1 is connected to the computer network system 7 through a connecting cable, and communicates with the water-cooled needle-shaped ablation electrode 4 through the water inlet and outlet pipes; the controllable radio frequency power source 2 is connected to the water-cooled needle-shaped ablation electrode 4 through the connecting cable , computer network system 7; the water-cooled needle-shaped ablation electrode 4 is installed on the No. 1 movable arm of the three-dimensional positioning system 3, and can be inserted into the target tissue of the patient during treatment; the ultrasonic imaging probe 5 is installed on the second arm of the three-dimensional positioning system. No. 1 movable arm, which can be in contact with the body surface above the target tissue of the patient during treatment, and is connected to the B-type ultrasonic imaging system 6 through the connecting cable; the B-type ultrasonic imaging system 6 is connected to the computer network system 7 through the connecting cable; the three-dimensional The positioning system 3 is a complex electromechanical system controlled by the computer network system 7, which is connected to the computer network system 7 through connecting cables; the man-machine dialogue peripherals 10 include keyboards, mice, etc., which are connected to the computer network system through respective connecting cables 7-phase connection; intelligent monitoring software 8 and treatment planning software 9 are installed in the memory of the computer network system 7; the computer network system 7 is respectively connected to the circulating water cooling device 1, the controllable radio frequency power source 2, and the three-dimensional positioning system 3 through connecting cables , B-type ultrasonic imaging system 6 are connected; the computer network system 7 can also read the preoperative CT image data and preoperative MR image data respectively through the network connection cable.

The circulating water cooling device adopts the existing equipment, wherein the return water pipe and the water outlet pipe are respectively connected with the water-cooled needle-shaped ablation electrode, and the control signal line and the temperature sensor are connected to the computer network system through connecting cables.

The controllable radio frequency power source adopts the existing circuit, the PWM signal from the computer network system is added to its control input terminal, and its output terminal outputs the controlled radio frequency power accordingly.

The water-cooled needle-shaped ablation electrode adopts an existing device. The connecting cable is connected with the main box through the cable plug, the radio frequency energy is input from the controllable radio frequency power source, and the temperature detection signal is output to the computer network system; the water inlet and outlet pipes are connected to the circulating water cooling device. The water-cooled needle-shaped ablation electrode is inserted into the target tissue, and the guide electrode is closely attached to the patient's buttocks or outer thighs. The two form a radio frequency circuit to perform radio frequency capacitive heating on the lesion.

The three-dimensional positioning system is a complex electromechanical system controlled by a computer network system, and consists of a bracket 11, a three-dimensional moving arm 12, a No. 1 movable arm 13, a No. 2 movable arm 14 and an electromagnetic tracking module 15. The support 11 is fixedly installed on the ground. The electromagnetic tracking module 15 is installed on the support 11, and the electromagnetic tracking module 15 is connected with the computer network system 7 and the three-dimensional motion arm 12 through a connecting cable, and is used to track the positions of the ultrasonic imaging probe 5, the water-cooled needle-shaped ablation electrode 4 and the human body, ensuring The coordinates of these three are unified. The three-dimensional moving arm 12 is connected to the support 11 and can move up and down, left and right, and forward and backward, so that the water-cooled needle-shaped ablation electrode 4 and the ultrasonic imaging probe 5 can quickly approach the target tissue. The No. 1 movable arm 13 is connected to the three-dimensional moving arm 12, and can perform precise three-dimensional movement, and the position error generated during the movement is not more than 1mm. The water-cooled needle-shaped ablation electrode 4 is detachably installed on the No. 1 movable arm 13 , and can be accurately inserted into the lesion by the movement of the No. 1 movable arm 13 . The second movable arm 14 is also connected to the three-dimensional movable arm 12. In addition to performing precise three-dimensional movement to make the ultrasonic imaging probe 5 accurately face the target tissue, it can also move in parallel to allow the ultrasonic imaging probe 5 to obtain the position of the target tissue. A series of images for use in reconstructing a 3D image. The three-dimensional positioning system provides sufficient degrees of freedom, and all dimensional movements are controlled by the computer network system.

The ultrasonic imaging probe 5 and B-type ultrasonic imaging system 6 are mature products, which directly transmit the acquired image information to the computer network system 7 .

The hardware platform of described computer network system 7 takes the high-grade microcomputer as the core, and is equipped with plug-in cards such as image acquisition card, multi-function data acquisition card, control card, Internet interface, PCI and ISA bus, USB interface, and storage has Intelligent monitoring software, treatment planning software, operating system is Windows XP.

The programming language of the intelligent monitoring software and treatment planning software is C ₊₊ .

The man-machine dialogue peripheral 10 includes a keyboard and a mouse, which are used to realize the interactive operation between the user and the computer, that is, manual intervention can be performed through the man-machine dialogue peripheral 10 .

The computer network system 7, man-machine dialogue peripherals 10, intelligent monitoring software 8 and treatment planning software 9 constitute a complete computer-aided surgery system.

Before the operation, the patient's lesion, that is, the target tissue, is firstly positioned by the ultrasonic imaging probe 5 and the B-type ultrasonic imaging system 6 installed on the second movable arm 14 of the three-dimensional positioning system 3 . After determining the position of the target tissue, further obtain the sequential tomographic images of the patient's target tissue, and then through image segmentation, extraction of isosurface and other processing, establish a 3D model and visualize it, and at the same time distinguish the structures of interest such as lesions, blood vessels, bones, etc. Ablation range. The three-dimensional model, that is, the position parameters x, y, z of each pixel in the reconstructed three-dimensional image, and the data of color parameters such as color value, hue, saturation, etc. are transmitted to the computer network system and stored, and it is used as the benchmark of the target tissue Model. Based on this, a treatment plan can be formulated: determine the needle insertion position, radiofrequency dose, cooling water temperature, etc. of the water-cooled radiofrequency ablation electrode needle. In addition, in order to achieve the connection and unification between the patient's body coordinates and the image coordinates, it is necessary to set ultrasound-sensitive marks on the surface of the human body. In order to achieve more precise treatment, the target tissue image can also be acquired by the CT imaging system or MR imaging system before operation, and the preoperative CT image data and preoperative MR image data can be fused with ultrasound images for multimodal information.

During the operation, the three-dimensional positioning system is adjusted according to the established treatment plan, and the water-cooled radiofrequency ablation electrode needle is inserted into the target tissue under the guidance of the ultrasound image. Then start the controllable radio frequency power source and the circulating water cooling device, the former outputs the radio frequency power according to the formulated treatment plan, that is, the radio frequency dose, and the latter keeps the temperature of the cooling water at the set value. At the same time, the image of the patient's target tissue is collected through the ultrasonic imaging probe and B-mode ultrasonic imaging system, and is registered with the 3D model established before the operation to reflect the color value, hue, saturation and other colors of each pixel in real time, accurately and dynamically The parameters change, and then determine the ablation status of the lesion, and accordingly issue corresponding instructions to adjust the working parameters of the controllable RF power source, that is, change the amplitude and working ratio of the RF output, so that the ablation treatment is in the best state. Such continuous acquisition, adjustment, re-acquisition, and re-adjustment means that the patient model and operation plan are continuously updated in time until the new target tissue model is consistent with the target tissue model set in the treatment plan when the treatment is completed. After the ablation treatment is completed, the all-in-one machine automatically terminates the treatment.

After surgery, images of the patient's target tissue are reacquired for a final assessment of treatment effectiveness.

Claims (2)

1. the water cooling type RFA employed tumor treatment integrated machine of an image guiding is characterized in that: be made up of circulating water cooling device (1), controlled radio frequency power source (2), 3 D positioning system (3), water-cooled needle-like ablating electrode (4), ultrasound imaging probe (5), B-mode ultrasonography system (6) and computer network system (7), Intellectualized monitoring software (8), therapy plot software (9) and human computer conversation's peripheral hardware (10); Described circulating water cooling device (1) is connected with computer network system (7) by connection cord, is connected with water-cooled needle-like ablating electrode (4) by inlet tube and outlet tube; Controlled radio frequency power source (2) is connected with water-cooled needle-like ablating electrode (4), computer network system (7) respectively by connection cord; Water-cooled needle-like ablating electrode (4) is installed on the lever arm of 3 D positioning system (3), is inserted into during treatment in patient's the target tissue; Ultrasound imaging probe (5) is installed on No. two lever arms of 3 D positioning system, and the body surface with patient's target tissue top during treatment contacts, and is connected with B-mode ultrasonography system (6) by connection cord; B-mode ultrasonography system (6) is connected with computer network system (7) by connection cord; 3 D positioning system (3) is a Mechatronic Systems that is subjected to computer network system (7) control, is connected with computer network system (7) by connection cord; The human computer conversation's peripheral hardware (10) that comprises keyboard, mouse is connected with computer network system (7) by connection cord; Intellectualized monitoring software (8), therapy plot software (9) are installed in the memorizer of computer network system (7); Computer network system (7) is connected with circulating water cooling device (1), controlled radio frequency power source (2), 3 D positioning system (3), B-mode ultrasonography system (6) respectively by connection cord; Computer network system (7) also reads before the art MR image data before the CT image data and art respectively by the network connection cord; Described 3 D positioning system (3) is made up of support (11), three-dimensional motion arm (12), a lever arm (13), No. two lever arms (14) and electromagnetism tracking module (15); Support (11) fixed installation on the ground, electromagnetism tracking module (15) is installed on the support (11), electromagnetism tracking module (15) links to each other with three-dimensional motion arm (12) with computer network system (7) by connection cord, is used for following the tracks of the position of ultrasound imaging probe (5), water-cooled needle-like ablating electrode (4) and human body; Three-dimensional motion arm (12) is connected on the support (11), can move top to bottom, left and right, front and rear, makes water-cooled needle-like ablating electrode (4), ultrasound imaging probe (5) fast near target tissue; A lever arm (13) is connected on the three-dimensional motion arm (12), and water-cooled needle-like ablating electrode (4) is removably mounted on the lever arm (13), borrows the three-dimensional motion of a lever arm (13) to be properly inserted in intralesional; No. two lever arms (14) are connected on the three-dimensional motion arm (12), make ultrasound imaging probe (5) exactly towards target tissue by three-dimensional motion, and can obtain the image series of target tissue, use for reconstruction of three-dimensional images.

2. the water cooling type RFA employed tumor treatment integrated machine of image guiding as claimed in claim 1 is characterized in that described computer network system (7), human computer conversation's peripheral hardware (10), Intellectualized monitoring software (8) and therapy plot software (9) constitute a complete computer assisted surgery system; In computer network system (7), store by ultrasound imaging probe (5) and B-mode ultrasonography system (6) and obtain the sequence faultage image of patient target tissue and through image segmentation, extract contour surface and handle the preceding benchmark model of the art of setting up the back, by radio-frequency power and the cooling water temperature in the therapeutic scheme control operation of formulating, gather the image of patient target tissue in real time, and make it with art before the benchmark model registration, the parameter that goes out according to dynamic reflection changes the situation that melts of judging focus, and regulate and control the running parameter of controlled radio frequency power source (2) in view of the above, promptly change the amplitude and the work ratio of radio frequency output, make ablation be in optimum state.

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