Series pulse sequence-based boiling histotripsy method and system

Abstract

The present application provides a series pulse sequence-based boiling histotripsy method and system. The method comprises: transmitting a series pulse sequence to a target tissue and monitoring a treatment process of boiling histotripsy. The treatment process of boiling histotripsy comprises: on the basis of the series pulse sequence, generating boiling bubbles and cavitation clouds in the target tissue and promoting the boiling bubbles and the cavitation clouds to collapse, causing mechanical damage in the target tissue, and displaying, in real time on an ultrasonic image, an echo region indicating generation of the boiling bubbles and the cavitation clouds; and removing, on the basis of the series pulse sequence, residual bubbles generated after the boiling bubbles and the cavitation clouds collapse and existing in the mechanical damage, and displaying, in real time on the ultrasonic image, an echo region indicating the mechanical damage occurring in the target tissue. Therefore, the operator can immediately observe the effect of mechanical ablation of the target tissue on the ultrasonic image after the treatment with boiling histotripsy, that is, the morphology and size of the echo region representing the mechanical damage to the target tissue. In addition, the efficiency of mechanical ablation of the target tissue is improved.

Description

A method and system for boiling tissue destruction based on tandem pulse sequences Technical Field

[0001] This application relates to the field of ultrasonic tissue destruction technology, and in particular to a boiling tissue destruction method and system based on a series of pulse sequences. Background Technology

[0002] The medical trend is gradually moving towards minimally invasive and non-invasive surgery, and ultrasonic tissue ablation is a non-invasive, non-ionizing, and non-thermal ablation technique that has emerged in recent years. The principle of boiling tissue ablation is as follows: Due to the nonlinear effect of ultrasound propagation, the shock wave formed at the focal point of high-intensity focused ultrasound can raise the tissue temperature to boiling within the first few milliseconds, generating a boiling bubble at the focal point. This boiling bubble interacts with the shock wave and expands to millimeter size through rectification and diffusion. The shear stress generated around this ever-growing boiling bubble can mechanically divide the surrounding soft tissue. Due to the shock scattering effect, an inertial cavitation cloud is generated in front of the boiling bubble and extends towards the transducer. With the generation of the inertial cavitation cloud, additional boiling bubbles can be formed within the focal region of the high-intensity focused ultrasound through incident wave diffraction. In soft tissue, the damage produced by boiling tissue ablation resembles a tadpole, consisting of a head and a tail. The shear force from the boiling bubble represents the tail, and the damage from the inertial cavitation cloud represents the head. Although boiling bubbles are generated through heating, the heat is confined to the focal area and does not diffuse into nearby tissues. Because the ultrasonic pulses used in boiling tissue destruction are controlled at the millisecond level and have a low duty cycle, it does not cause thermal tissue necrosis.

[0003] Operators typically use tens to hundreds of high-power, low-duty-cycle millisecond-level pulses to perform boiling tissue destruction on the target tissue. The boiling bubbles and cavitation clouds generated by these millisecond pulses produce hyperechoic areas during each pulse, appearing as brighter regions on ultrasound images. The interaction between the ultrasound and the bubbles causes the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue. This mechanical damage is accompanied by numerous tiny residual bubbles within the damaged area. On ultrasound images, the mechanical damage appears hypoechoic, while the residual bubbles are hyperechoic. Therefore, the hyperechoic areas of the residual bubbles and the hypoechoic areas of the mechanical damage are mixed together, resulting in the mechanical damage area remaining hyperechoic after boiling tissue destruction treatment. However, because the bubble dissolution time is relatively long, the hypoechoic area representing the mechanical damage is not immediately visible on ultrasound images after each pulse; it only appears some time after the boiling tissue destruction treatment has ended. Therefore, the operator cannot observe the ablation of the target tissue by each pulse in real time in the ultrasound image, nor can they observe the effect of the boiling tissue destruction technique on the mechanical ablation of the target tissue immediately after treatment.

[0004] Summary of the Invention

[0005] In view of the shortcomings of the above-mentioned related technologies, the purpose of this application is to provide a method and system for boiling tissue destruction based on a series pulse sequence, so as to solve the technical problems existing in the observation of echo regions in the related technologies.

[0006] To achieve the above and other related objectives, this application provides a method for boiling tissue destruction based on a series of pulse sequences, comprising the following steps:

[0007] A series pulse sequence is generated by a focused ultrasound transducer;

[0008] The tandem pulse sequence is transmitted to a target tissue, and the boiling tissue destruction treatment process is monitored by an ultrasound probe; wherein the boiling tissue destruction treatment process includes: generating boiling bubbles and cavitation clouds in the target tissue based on the tandem pulse sequence, and causing the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage in the target tissue; and removing residual bubbles present in the mechanical damage after the collapse of the boiling bubbles and cavitation clouds based on the tandem pulse sequence.

[0009] The ultrasound image displays in real time a first echo region representing the boiling bubbles and cavitation clouds generated during the boiling tissue destruction treatment, and a second echo region representing mechanical damage to the target tissue during the boiling tissue destruction treatment.

[0010] In one embodiment of this application, the tandem pulse sequence includes a first pulse sequence and a second pulse sequence;

[0011] The first pulse sequence is used to generate the boiling bubbles and the cavitation cloud in the target tissue and cause the boiling bubbles and the cavitation cloud to collapse, resulting in mechanical damage in the target tissue.

[0012] The second pulse sequence is used to remove the boiling bubbles and residual bubbles present in the mechanical damage generated after the collapse of the cavitation cloud.

[0013] In one embodiment of this application, the power of the first pulse sequence and the second pulse sequence are different, the duty cycle of the first pulse sequence and the second pulse sequence are different, and the pulse working time of the first pulse sequence and the second pulse sequence are different.

[0014] In one embodiment of this application, the power of the first pulse sequence is greater than the power of the second pulse sequence, the duty cycle of the first pulse sequence is less than the duty cycle of the second pulse sequence, and the pulse working time of the first pulse sequence is less than the pulse working time of the second pulse sequence.

[0015] In one embodiment of this application, the acoustic power range of the first pulse sequence includes 1000W-5000W, the duty cycle of the first pulse sequence is less than 2%, and the pulse working time of the first pulse sequence is less than 20ms.

[0016] The acoustic power range of the second pulse sequence is 100W-400W, the duty cycle range is 5%-20%, and the pulse working time range is 100ms-500ms.

[0017] In one embodiment of this application, the first pulse sequence is a millisecond-level pulse sequence containing multiple pulses, and the second pulse sequence is a millisecond-level pulse sequence containing multiple pulses.

[0018] In one embodiment of this application, the ultrasound probe includes a B-mode ultrasound probe, and the ultrasound image includes a B-mode ultrasound image.

[0019] In one embodiment of this application, the brightness of the first echo region on the ultrasound image is higher than a predetermined reference brightness, and the brightness of the second echo region on the ultrasound image is lower than the reference brightness.

[0020] This application also provides a boiling tissue destruction system based on a series of pulse sequences, the system comprising:

[0021] A signal generator is used to provide an electrical excitation signal;

[0022] A power amplifier, connected to the signal generator, is used to amplify the electrical excitation signal provided by the signal generator.

[0023] A focused ultrasound transducer, connected to the power amplifier, is used to transmit a series of pulses in response to the gain-enhanced electrical excitation signal output by the power amplifier, and transmit them to the target tissue for a boiling tissue destruction treatment process; wherein the boiling tissue destruction treatment process includes: generating boiling bubbles and cavitation clouds in the target tissue based on the series of pulses, and causing the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage in the target tissue; and removing residual bubbles present in the mechanical damage after the collapse of the boiling bubbles and cavitation clouds based on the series of pulses.

[0024] An ultrasound probe, connected to the focused ultrasound transducer, is used to monitor the boiling tissue destruction treatment process and to display in real time on the ultrasound image a first echo region representing the boiling bubbles and cavitation clouds generated during the boiling tissue destruction treatment process, and a second echo region representing mechanical damage to the target tissue during the boiling tissue destruction treatment process.

[0025] In one embodiment of this application, the tandem pulse sequence includes a first pulse sequence and a second pulse sequence;

[0026] The first pulse sequence is used to generate the boiling bubbles and the cavitation cloud in the target tissue and to cause the boiling bubbles and the cavitation cloud to collapse, thereby causing mechanical damage in the target tissue.

[0027] The second pulse sequence is used to remove the boiling bubbles and residual bubbles present in the mechanical damage generated after the collapse of the cavitation cloud;

[0028] The first pulse sequence and the second pulse sequence have different powers, different duty cycles, and different pulse working times.

[0029] As described above, this application provides a method and system for boiling tissue destruction based on a series pulse sequence, which has the following beneficial effects:

[0030] This application utilizes a tandem pulse sequence in a boiling tissue destruction technique. This tandem pulse sequence can be designed to use a first pulse sequence followed by a second pulse sequence, and this cycle is repeated multiple times. The power of the first pulse sequence is greater than that of the second pulse sequence, the duty cycle of the first pulse sequence is smaller than that of the second pulse sequence, and the pulse duration of the first pulse sequence is shorter than that of the second pulse sequence. The first pulse sequence is used to generate boiling bubbles and cavitation clouds in the target tissue and to cause them to collapse, resulting in mechanical damage. The second pulse sequence is used to remove residual bubbles present in the mechanical damage after the boiling bubbles and cavitation clouds collapse. During each cycle of the tandem pulse sequence, the operator can observe in real-time the flickering of a first echo region during the generation of boiling bubbles and cavitation clouds in the ultrasound image during the first pulse sequence, and can also observe in real-time the appearance of a second echo region representing mechanical damage to the target tissue in the ultrasound image after the second pulse sequence output. The brightness of the first echo region on the ultrasound image is higher than a predetermined reference brightness, while the brightness of the second echo region on the ultrasound image is lower than the reference brightness. Therefore, the operator can immediately observe the effect of mechanical ablation of the target tissue on ultrasound imaging after the boiling tissue destruction procedure, that is, the shape and size of the second echo zone representing the mechanical damage of the target tissue, and increase the efficiency of mechanical ablation of the target tissue. Attached Figure Description

[0031] Figure 1 is a schematic diagram of the traditional pulse sequence used in the boiling tissue destruction therapy;

[0032] Figure 2 is a schematic diagram of the gray value changes of pixels at the focal point on ultrasound images during and after the treatment of target tissue using traditional pulse sequence for boiling tissue destruction.

[0033] Figure 3 is a schematic diagram of a boiling tissue destruction method based on a series pulse sequence provided in this application;

[0034] Figure 4 is a schematic diagram of a B-mode ultrasound image of a target tissue during the first pulse sequence provided in this application;

[0035] Figure 5 is a schematic diagram of a B-ultrasound image of a target tissue after treatment using a tandem pulse sequence provided in this application.

[0036] Figure 6 is a schematic diagram of the actual damage to a target tissue after treatment using a tandem pulse sequence provided in this application.

[0037] Figure 7 is a schematic diagram of the ultrasound image of the ex vivo bovine liver provided in this application during the first pulse sequence;

[0038] Figure 8 is a schematic diagram of an ultrasound image of an ex vivo bovine liver after treatment using a tandem pulse sequence, as provided in this application.

[0039] Figure 9 is a schematic diagram of the actual damage to the isolated bovine liver after treatment using a tandem pulse sequence provided in this application.

[0040] Figure 10 is a schematic diagram of a tandem pulse sequence provided in this application;

[0041] Figure 11 is a schematic diagram of the hardware structure of a boiling tissue destruction system based on a series pulse sequence provided in this application. Detailed Implementation

[0042] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0043] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this application. The illustrations only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0044] In this technique, the operator uses a traditional pulse sequence to perform boiling tissue destruction on the target tissue. During the pulse output, a flickering effect representing the hyperechoic area generated by boiling bubbles and cavitation clouds can be observed on ultrasound images; that is, the grayscale value of the pixel at the focal point increases during treatment. The interaction between ultrasound and the bubbles causes the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue. This mechanical damage is accompanied by numerous tiny residual bubbles within the damaged area. In ultrasound images, the mechanical damage appears hypoechoic, while the residual bubbles are hyperechoic. Therefore, the hyperechoic residual bubbles and hypoechoic mechanical damage mix together in the ultrasound image, causing the mechanical damage area to remain hyperechoic after boiling tissue destruction treatment. Due to the long dissolution time of the bubbles, the hypoechoic area representing the mechanical damage cannot be immediately observed on ultrasound images after the boiling tissue destruction treatment; that is, the grayscale value of the pixel at the focal point on the ultrasound image slowly decreases from a high grayscale value to near 0, typically appearing on ultrasound images about 5 minutes after treatment. As shown in Figures 1 and 2, Figure 1 shows a schematic diagram of the conventional pulse sequence used in the boiling tissue destruction treatment. As shown in Figure 1, the number of conventional pulse sequences can be represented as n. Figure 2 shows a schematic diagram of the gray value changes of pixels at the focal point on ultrasound images during and after the boiling tissue destruction treatment using conventional pulse sequences.

[0045] Figure 3 shows a schematic flowchart of a boiling tissue destruction method based on a series of pulse sequences. Specifically, in an exemplary embodiment, as shown in Figure 3, this embodiment provides a boiling tissue destruction method based on a series of pulse sequences, which includes the following steps:

[0046] S310, a series pulse sequence is generated using a focused ultrasound transducer. In this embodiment or other embodiments, the focused ultrasound transducer is a scientific and technological instrument used in clinical treatment. As an example, the process of generating a series pulse sequence using a focused ultrasound transducer in this embodiment may include: providing an electrical excitation signal using a signal generator, connecting a power amplifier to the signal generator, and using the power amplifier to amplify the electrical excitation signal provided by the signal generator; then connecting the focused ultrasound transducer to the power amplifier so that the focused ultrasound transducer generates an ultrasound series pulse sequence based on the amplified electrical excitation signal output by the power amplifier.

[0047] S320, a series of pulse sequences are transmitted to a target tissue, and the boiling tissue destruction treatment process is monitored by an ultrasound probe; wherein, the boiling tissue destruction treatment process includes: generating boiling bubbles and cavitation clouds in the target tissue based on the series of pulse sequences, and causing the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage in the target tissue; and removing residual bubbles present in the mechanical damage after the collapse of the boiling bubbles and cavitation clouds based on the series of pulse sequences. In this embodiment or other embodiments, the target tissue can be selected or determined according to the actual situation. As an example, the target tissue may be an excised bovine liver. As another example, the target tissue may be tumor tissue. As yet another example, the target tissue may be a clot or hematoma. In this embodiment or other embodiments, the ultrasound probe may be a B-mode ultrasound probe.

[0048] S330, The ultrasound image displays in real-time a first echo region indicating the generation of boiling bubbles and cavitation clouds during the boiling tissue destruction treatment process, and a second echo region indicating mechanical damage to the target tissue during the boiling tissue destruction treatment process. In this embodiment or other embodiments, the ultrasound image can be a B-mode ultrasound image. In this embodiment or other embodiments, the brightness of the first echo region on the ultrasound image is higher than a predetermined reference brightness, and the brightness of the second echo region on the ultrasound image is lower than the reference brightness. The reference brightness can be the normal brightness of the ultrasound image determined in advance or in real-time. In this embodiment or other embodiments, the first echo region can also be referred to as a hyperechoic region, and the second echo region can also be referred to as a hypoechoic region.

[0049] This embodiment uses a series of pulse sequences in the boiling tissue ablation technique, allowing the operator to immediately observe the effect of mechanical ablation of the target tissue on ultrasound images after the boiling tissue ablation treatment. This includes the shape and size of the second echo region representing the mechanical damage to the target tissue, thus solving the problem that related technologies cannot observe the effect of boiling tissue ablation on the mechanical ablation of the target tissue in real time.

[0050] In one exemplary embodiment, the tandem pulse sequence can consist of a first pulse sequence and a second pulse sequence. The first pulse sequence can be used to generate boiling bubbles and cavitation clouds in the target tissue, and cause the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue. The second pulse sequence can be used to remove residual bubbles present in the mechanical damage after the boiling bubbles and cavitation clouds collapse. Specifically, the initial pulse in the first pulse sequence generates boiling bubbles and cavitation clouds at the focal point, and subsequent ultrasonic pulses interact with the boiling bubbles and cavitation clouds, causing them to collapse and resulting in mechanical damage. Because the collapse of boiling bubbles and cavitation clouds causes mechanical damage, it also generates numerous tiny residual bubbles. These residual bubbles exist within the mechanical damage. Since the mechanical damage is essentially liquefied, homogeneous tissue fragments, it appears as hypoechoic on ultrasound images. However, boiling bubbles, cavitation clouds, and residual bubbles all appear as hyperechoic on ultrasound images. Therefore, when the hyperechoic residual bubbles and the hypoechoic mechanical damage are mixed together on ultrasound images, the mechanical damage area remains hyperechoic after boiling tissue ablation treatment. The dissolution of residual bubbles takes several minutes, meaning that the residual bubbles in the mechanical damage will only dissolve after several minutes, at which point the mechanical damage will appear as a hypoechoic area on ultrasound images. Only then can the treatment effect be assessed through imaging. Therefore, this embodiment introduces a second pulse sequence to remove the residual bubbles present in the mechanical damage after the collapse of boiling bubbles and cavitation clouds, ensuring that the operator can immediately observe the effect of mechanical ablation of the target tissue on ultrasound images after boiling tissue ablation treatment. In this embodiment or other embodiments, the tandem pulse sequence can be designed to use a first pulse sequence followed by a second pulse sequence, and so on, in multiple cycles. During each cycle of the tandem pulse sequence, the operator can observe in real-time the flickering of the first echo region during the generation of boiling bubbles and cavitation clouds in the ultrasound image, and can also observe in real-time the appearance of the second echo region representing mechanical damage to the target tissue in the ultrasound image after the second pulse sequence output. Therefore, the operator can immediately observe the effect of mechanical ablation of the target tissue on the ultrasound image after the boiling tissue destruction treatment, i.e., the shape and size of the second echo region representing mechanical damage to the target tissue. In this embodiment or other embodiments, Figure 4 shows a schematic diagram of a B-mode ultrasound image of a target tissue during the first pulse sequence. Therefore, when using a tandem pulse sequence for boiling tissue destruction treatment, in each cycle of the tandem wave, the first pulse sequence is used to generate boiling bubbles and cavitation clouds in the target tissue, and to cause the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue; the flickering of the first echo region can be observed in the B-mode ultrasound image during the first pulse sequence, as shown in Figure 4. The second pulse sequence is used after the first pulse sequence to remove residual bubbles present in mechanical damage caused by boiling bubbles and cavitation cloud collapse.After treatment, the second echo region, morphology, and size representing mechanical damage to the target tissue can be immediately observed on ultrasound imaging. Figures 5 and 6 illustrate this. Figure 5 shows a schematic ultrasound image of a target tissue after treatment using a tandem pulse sequence. Figure 6 shows a schematic diagram of the actual damage to the target tissue after treatment using a tandem pulse sequence. As an example, if the target tissue is an excised bovine liver, the schematic ultrasound image of the excised bovine liver during the first pulse sequence is shown in Figure 7, where the arrow in Figure 7 points to the first echo region. The schematic ultrasound image of the excised bovine liver after treatment using a tandem pulse sequence is shown in Figure 8, where the arrow in Figure 8 points to the second echo region. The schematic diagram of the actual damage to the excised bovine liver after treatment using a tandem pulse sequence is shown in Figure 9, where the arrow in Figure 9 points to the morphology and size of the mechanical damage to the excised bovine liver.

[0051] In an exemplary embodiment, the cascaded pulse sequence can be composed of a first pulse sequence and a second pulse sequence. The first pulse sequence and the second pulse sequence have different powers, different duty cycles, and different pulse operating times. In this embodiment or other embodiments, the first pulse sequence can be a millisecond-level pulse sequence containing multiple pulses, and the second pulse sequence can be a millisecond-level pulse sequence containing multiple pulses. Figure 10 shows a schematic diagram of a cascaded pulse sequence. As shown in Figure 10, the first pulse sequence is represented as n1, and the second pulse sequence is represented as n2. The first pulse sequence has an acoustic power range of 1000W-5000W, a duty cycle of less than 2%, and a pulse operating time of less than 20ms; the second pulse sequence has an acoustic power range of 100W-400W, a duty cycle range of 5%-20%, and a pulse operating time range of 100ms-500ms.

[0052] In an exemplary embodiment, the cascaded pulse sequence can be composed of a first pulse sequence and a second pulse sequence. The power of the first pulse sequence is greater than that of the second pulse sequence, the duty cycle of the first pulse sequence is less than that of the second pulse sequence, and the pulse operating time of the first pulse sequence is less than that of the second pulse sequence. In this embodiment or other embodiments, the first pulse sequence can be a millisecond-level pulse sequence containing multiple pulses, and the second pulse sequence can be a millisecond-level pulse sequence containing multiple pulses. Figure 10 shows a schematic diagram of a cascaded pulse sequence. As shown in Figure 10, the first pulse sequence is denoted as n1, and the second pulse sequence is denoted as n2. The acoustic power range of the first pulse sequence includes 1000W-5000W, the duty cycle of the first pulse sequence is less than 2%, and the pulse operating time of the first pulse sequence is less than 20ms; the acoustic power range of the second pulse sequence includes 100W-400W, the duty cycle of the second pulse sequence ranges from 5% to 20%, and the pulse operating time ranges from 100ms to 500ms.

[0053] In summary, this application provides a method for boiling tissue destruction based on a series of pulse sequences. The method utilizes a series of pulse sequences, which can be designed to use a first pulse sequence followed by a second pulse sequence, and so on, in multiple cycles. Specifically, the power of the first pulse sequence is greater than that of the second pulse sequence, the duty cycle of the first pulse sequence is smaller than that of the second pulse sequence, and the pulse duration of the first pulse sequence is shorter than that of the second pulse sequence. The first pulse sequence is used to generate boiling bubbles and cavitation clouds in the target tissue and to cause them to collapse, resulting in mechanical damage. The second pulse sequence is used to remove residual bubbles present in the mechanical damage after the boiling bubbles and cavitation clouds collapse. During each cascaded pulse sequence cycle, the operator can observe in real-time the flickering of the first echo region during the generation of boiling bubbles and cavitation clouds in the ultrasound image during the first pulse sequence, and can also observe in real-time the appearance of the second echo region representing mechanical damage to the target tissue in the ultrasound image after the second pulse sequence output. The brightness of the first echo region on the ultrasound image is higher than a predetermined reference brightness, while the brightness of the second echo region is lower than the reference brightness. Therefore, the operator can immediately observe the effect of mechanical ablation of the target tissue on the ultrasound image after the boiling tissue destruction treatment, i.e., the morphology and size of the second echo region representing mechanical damage to the target tissue, thus increasing the efficiency of mechanical ablation of the target tissue.

[0054] In another exemplary embodiment of this application, as shown in FIG11, this embodiment also provides a boiling tissue destruction system based on a series pulse sequence, comprising:

[0055] A signal generator is used to provide an electrical excitation signal;

[0056] A power amplifier, connected to a signal generator, is used to increase the gain of the electrical excitation signal provided by the signal generator;

[0057] A focused ultrasound transducer, connected to a power amplifier, is used to transmit a series of pulses in response to the amplified electrical excitation signal output by the power amplifier, and transmit this pulses to the target tissue for a boiling tissue destruction treatment process. The boiling tissue destruction treatment process includes: generating boiling bubbles and cavitation clouds in the target tissue based on the series pulse sequence, and causing the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue; and removing residual bubbles present in the mechanical damage after the collapse of the boiling bubbles and cavitation clouds based on the series pulse sequence.

[0058] An ultrasound probe, connected to a focused ultrasound transducer, is used to monitor the treatment process of boiling tissue destruction and to display in real time on ultrasound images the first echo region indicating the generation of boiling bubbles and cavitation clouds during the treatment process, and the second echo region indicating mechanical damage to the target tissue during the treatment process.

[0059] In addition, the echo zone display system may also include a control terminal connected to a signal generator for setting parameters so that the signal generator provides an electrical excitation signal according to the set parameters.

[0060] This embodiment uses a series of pulse sequences in the boiling tissue ablation technique, allowing the operator to immediately observe the effect of mechanical ablation of the target tissue on ultrasound images after the boiling tissue ablation treatment. This includes the shape and size of the second echo region representing the mechanical damage to the target tissue, thus solving the problem that related technologies cannot observe the effect of boiling tissue ablation on the mechanical ablation of the target tissue in real time.

[0061] In one exemplary embodiment, the tandem pulse sequence can consist of a first pulse sequence and a second pulse sequence. The first pulse sequence can be used to generate boiling bubbles and cavitation clouds in the target tissue, and cause the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue. The second pulse sequence can be used to remove residual bubbles present in the mechanical damage after the boiling bubbles and cavitation clouds collapse. Specifically, the initial pulse in the first pulse sequence generates boiling bubbles and cavitation clouds at the focal point, and subsequent ultrasonic pulses interact with the boiling bubbles and cavitation clouds, causing them to collapse and resulting in mechanical damage. Because the collapse of boiling bubbles and cavitation clouds causes mechanical damage, it also generates numerous tiny residual bubbles. These residual bubbles exist within the mechanical damage. Since the mechanical damage is essentially liquefied, homogeneous tissue fragments, it appears as hypoechoic on ultrasound images. However, boiling bubbles, cavitation clouds, and residual bubbles all appear as hyperechoic on ultrasound images. Therefore, when the hyperechoic residual bubbles and the hypoechoic mechanical damage are mixed together on ultrasound images, the mechanical damage area remains hyperechoic after boiling tissue ablation treatment. The dissolution of residual bubbles takes several minutes, meaning that the residual bubbles in the mechanical damage will only dissolve after several minutes, at which point the mechanical damage will appear as a hypoechoic area on ultrasound images. Only then can the treatment effect be assessed through imaging. Therefore, this embodiment introduces a second pulse sequence to remove the residual bubbles present in the mechanical damage after the collapse of boiling bubbles and cavitation clouds, ensuring that the operator can immediately observe the effect of mechanical ablation of the target tissue on ultrasound images after boiling tissue ablation treatment. In this embodiment or other embodiments, the tandem pulse sequence can be designed to use a first pulse sequence followed by a second pulse sequence, and so on, in multiple cycles. During each cycle of the tandem pulse sequence, the operator can observe in real-time the flickering of the first echo region during the generation of boiling bubbles and cavitation clouds in the ultrasound image, and can also observe in real-time the appearance of the second echo region representing mechanical damage to the target tissue in the ultrasound image after the second pulse sequence output. Therefore, the operator can immediately observe the effect of mechanical ablation of the target tissue on the ultrasound image after the boiling tissue destruction treatment, i.e., the shape and size of the second echo region representing mechanical damage to the target tissue. In this embodiment or other embodiments, Figure 4 shows a schematic diagram of a B-mode ultrasound image of a target tissue during the first pulse sequence. Therefore, when using a tandem pulse sequence for boiling tissue destruction treatment, in each cycle of the tandem wave, the first pulse sequence is used to generate boiling bubbles and cavitation clouds in the target tissue, and to cause the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage to the target tissue; the flickering of the first echo region can be observed in the B-mode ultrasound image during the first pulse sequence, as shown in Figure 4. The second pulse sequence is used after the first pulse sequence to remove residual bubbles present in mechanical damage caused by boiling bubbles and cavitation cloud collapse.After treatment, the second echo region, morphology, and size representing mechanical damage to the target tissue can be immediately observed on ultrasound imaging. Figures 5 and 6 illustrate this. Figure 5 shows a schematic ultrasound image of a target tissue after treatment using a tandem pulse sequence. Figure 6 shows a schematic diagram of the actual damage to the target tissue after treatment using a tandem pulse sequence. As an example, if the target tissue is an excised bovine liver, the schematic ultrasound image of the excised bovine liver during the first pulse sequence is shown in Figure 7, where the arrow in Figure 7 points to the first echo region. The schematic ultrasound image of the excised bovine liver after treatment using a tandem pulse sequence is shown in Figure 8, where the arrow in Figure 8 points to the second echo region. The schematic diagram of the actual damage to the excised bovine liver after treatment using a tandem pulse sequence is shown in Figure 9, where the arrow in Figure 9 points to the morphology and size of the mechanical damage to the excised bovine liver.

[0062] In an exemplary embodiment, the cascaded pulse sequence can be composed of a first pulse sequence and a second pulse sequence. The first pulse sequence and the second pulse sequence have different powers, different duty cycles, and different pulse operating times. In this embodiment or other embodiments, the first pulse sequence can be a millisecond-level pulse sequence containing multiple pulses, and the second pulse sequence can be a millisecond-level pulse sequence containing multiple pulses. Figure 10 shows a schematic diagram of a cascaded pulse sequence. As shown in Figure 10, the first pulse sequence is represented as n1, and the second pulse sequence is represented as n2. The first pulse sequence has an acoustic power range of 1000W-5000W, a duty cycle of less than 2%, and a pulse operating time of less than 20ms; the second pulse sequence has an acoustic power range of 100W-400W, a duty cycle range of 5%-20%, and a pulse operating time range of 100ms-500ms.

[0063] In an exemplary embodiment, the cascaded pulse sequence can be composed of a first pulse sequence and a second pulse sequence. The power of the first pulse sequence is greater than that of the second pulse sequence, the duty cycle of the first pulse sequence is less than that of the second pulse sequence, and the pulse operating time of the first pulse sequence is less than that of the second pulse sequence. In this embodiment or other embodiments, the first pulse sequence can be a millisecond-level pulse sequence containing multiple pulses, and the second pulse sequence can be a millisecond-level pulse sequence containing multiple pulses. Figure 10 shows a schematic diagram of a cascaded pulse sequence. As shown in Figure 10, the first pulse sequence is denoted as n1, and the second pulse sequence is denoted as n2. The acoustic power range of the first pulse sequence includes 1000W-5000W, the duty cycle of the first pulse sequence is less than 2%, and the pulse operating time of the first pulse sequence is less than 20ms; the acoustic power range of the second pulse sequence includes 100W-400W, the duty cycle of the second pulse sequence ranges from 5% to 20%, and the pulse operating time ranges from 100ms to 500ms.

[0064] In summary, this application provides a boiling tissue ablation system based on a series of pulse sequences. The system utilizes a signal generator to provide an electrical excitation signal, and connects a power amplifier to the signal generator to amplify the electrical excitation signal. A focused ultrasound transducer is also connected to the power amplifier, generating a series of pulse sequences based on the amplified electrical excitation signal output from the power amplifier. These sequences are then transmitted to the target tissue for boiling tissue ablation treatment. Furthermore, an ultrasound probe is connected to the focused ultrasound transducer to monitor the boiling tissue ablation treatment process. The probe displays, in real-time, a first echo region indicating the generation of boiling bubbles and cavitation clouds, and a second echo region indicating mechanical damage to the target tissue. Therefore, this echo region display system achieves this by using a series of pulse sequences during boiling tissue ablation, which can be designed to use a first pulse sequence followed by a second pulse sequence, and so on, in multiple cycles. In this sequence, the power of the first pulse sequence is greater than that of the second pulse sequence, the duty cycle of the first pulse sequence is smaller than that of the second pulse sequence, and the pulse duration of the first pulse sequence is shorter than that of the second pulse sequence. The first pulse sequence is used to generate boiling bubbles and cavitation clouds in the target tissue and to cause them to collapse, resulting in mechanical damage to the target tissue. The second pulse sequence is used to remove residual bubbles present in the mechanical damage after the boiling bubbles and cavitation clouds collapse. During each cycle of the tandem pulse sequence, the operator can observe in real-time the flickering of the first echo region during the generation of boiling bubbles and cavitation clouds in the ultrasound image during the first pulse sequence, and can also observe in real-time the appearance of the second echo region representing mechanical damage to the target tissue in the ultrasound image after the second pulse sequence output. The brightness of the first echo region on the ultrasound image is higher than a predetermined reference brightness, while the brightness of the second echo region on the ultrasound image is lower than the reference brightness. Therefore, the operator can immediately observe the effect of mechanical ablation of the target tissue on the ultrasound image after the boiling tissue destruction treatment, i.e., the morphology and size of the second echo region representing mechanical damage to the target tissue.

[0065] It should be noted that the above embodiments, in collecting, storing, using, processing, transmitting, providing, disclosing, and deleting relevant data (such as ultrasound images), are carried out with or with the user's consent. For example, ultrasound images may be obtained with the user's knowledge and consent; or they may be provided voluntarily by the user after reading the relevant instructions; or they may be actively authorized / provided / uploaded by the user when using some or all of the functions described in the above embodiments; or they may be obtained through other means or channels with or with the user's consent.

[0066] It should be understood that although terms such as "first," "second," etc., may be used to describe echo regions in the embodiments of this application, these terms are only used to distinguish echo regions from each other. For example, without departing from the scope of the embodiments of this application, a first echo region may also be referred to as a second echo region, and similarly, a second echo region may also be referred to as a first echo region.

[0067] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A method for boiling tissue destruction based on a series of pulse sequences, wherein, The method includes the following steps: A series pulse sequence is generated by a focused ultrasound transducer; The tandem pulse sequence is transmitted to a target tissue, and the boiling tissue destruction treatment process is monitored by an ultrasound probe; wherein the boiling tissue destruction treatment process includes: generating boiling bubbles and cavitation clouds in the target tissue based on the tandem pulse sequence, and causing the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage in the target tissue; and removing residual bubbles present in the mechanical damage after the collapse of the boiling bubbles and cavitation clouds based on the tandem pulse sequence. The ultrasound image displays in real time a first echo region representing the boiling bubbles and cavitation clouds generated during the boiling tissue destruction treatment, and a second echo region representing mechanical damage to the target tissue during the boiling tissue destruction treatment.

2. The method for boiling tissue destruction based on a series pulse sequence according to claim 1, wherein, The cascaded pulse sequence includes a first pulse sequence and a second pulse sequence; The first pulse sequence is used to generate the boiling bubbles and the cavitation cloud in the target tissue and cause the boiling bubbles and the cavitation cloud to collapse, resulting in mechanical damage in the target tissue. The second pulse sequence is used to remove the boiling bubbles and residual bubbles present in the mechanical damage generated after the collapse of the cavitation cloud.

3. The method for boiling tissue destruction based on a series pulse sequence according to claim 2, wherein, The first pulse sequence and the second pulse sequence have different powers, different duty cycles, and different pulse working times.

4. The boiling tissue destruction method based on a tandem pulse sequence according to claim 2 or 3, wherein, The power of the first pulse sequence is greater than the power of the second pulse sequence, the duty cycle of the first pulse sequence is less than the duty cycle of the second pulse sequence, and the pulse working time of the first pulse sequence is less than the pulse working time of the second pulse sequence.

5. The boiling tissue destruction method based on a tandem pulse sequence according to any one of claims 2 to 4, wherein, The acoustic power range of the first pulse sequence is 1000W-5000W, the duty cycle of the first pulse sequence is less than 2%, and the pulse working time of the first pulse sequence is less than 20ms. The acoustic power range of the second pulse sequence is 100W-400W, the duty cycle range is 5%-20%, and the pulse working time range is 100ms-500ms.

6. The boiling tissue destruction method based on a tandem pulse sequence according to any one of claims 2 to 5, wherein, The first pulse sequence comprises multiple millisecond-level pulse sequences, and the second pulse sequence comprises multiple millisecond-level pulse sequences.

7. The boiling tissue destruction method based on a tandem pulse sequence according to any one of claims 1 to 6, wherein, The ultrasound probe includes a B-mode ultrasound probe, and the ultrasound image includes a B-mode ultrasound image.

8. The boiling tissue destruction method based on a tandem pulse sequence according to any one of claims 1 to 7, wherein, The brightness of the first echo region on the ultrasound image is higher than a predetermined reference brightness, and the brightness of the second echo region on the ultrasound image is lower than the reference brightness.

9. A boiling tissue destruction system based on a series of pulse sequences, wherein, The system includes: A signal generator is used to provide an electrical excitation signal; A power amplifier, connected to the signal generator, is used to amplify the electrical excitation signal provided by the signal generator. A focused ultrasound transducer, connected to the power amplifier, is used to transmit a series of pulses in response to the gain-enhanced electrical excitation signal output by the power amplifier, and transmit them to the target tissue for a boiling tissue destruction treatment process; wherein the boiling tissue destruction treatment process includes: generating boiling bubbles and cavitation clouds in the target tissue based on the series of pulses, and causing the boiling bubbles and cavitation clouds to collapse, resulting in mechanical damage in the target tissue; and removing residual bubbles present in the mechanical damage after the collapse of the boiling bubbles and cavitation clouds based on the series of pulses. An ultrasound probe, connected to the focused ultrasound transducer, is used to monitor the boiling tissue destruction treatment process and to display in real time on the ultrasound image a first echo region representing the boiling bubbles and cavitation clouds generated during the boiling tissue destruction treatment process, and a second echo region representing mechanical damage to the target tissue during the boiling tissue destruction treatment process.

10. The boiling tissue destruction system based on a tandem pulse sequence according to claim 9, wherein, The cascaded pulse sequence includes a first pulse sequence and a second pulse sequence; The first pulse sequence is used to generate the boiling bubbles and the cavitation cloud in the target tissue and to cause the boiling bubbles and the cavitation cloud to collapse, thereby causing mechanical damage in the target tissue. The second pulse sequence is used to remove the boiling bubbles and residual bubbles present in the mechanical damage generated after the collapse of the cavitation cloud; The first pulse sequence and the second pulse sequence have different powers, different duty cycles, and different pulse working times.

Images