阅读说明：本技术 肿瘤消融仿真方法及系统 (Tumor ablation simulation method and system ) 是由 赵宇熙 周付根 于 2021-10-12 设计创作，主要内容包括：本发明公开了一种肿瘤消融仿真方法及系统,该方法包括：在医学影像中标记肿瘤目标,建立包含肿瘤目标TV区域的三维影像；在三维影像中生成包络肿瘤目标TV区域的布针区域,在布针区域设置若干针道,若干针道在布针区域无交点,在针道中设置微波放射源,微波放射源产生电磁场以消融肿瘤目标；计算电磁场覆盖的第一消融体积；设置消融参数,消融参数表征第一消融体积与肿瘤目标TV区域适形程度；修改针道数量、针道位置、微波放射源功率和工作时间中的至少一个参数,重新计算第一消融体积,以满足消融参数。本发明提出的技术方案仿真微波消融手术的治疗效果,为医师在手术前提供实施参考,缓解了对医师个人经验的高度依赖。(The invention discloses a tumor ablation simulation method and a system, wherein the method comprises the following steps: marking a tumor target in the medical image, and establishing a three-dimensional image containing a tumor target TV region; generating a needle distribution area enveloping a tumor target TV area in a three-dimensional image, arranging a plurality of needle ways in the needle distribution area, wherein the needle ways have no intersection points in the needle distribution area, arranging a microwave radioactive source in each needle way, and generating an electromagnetic field by the microwave radioactive source to ablate a tumor target; calculating a first ablation volume covered by an electromagnetic field; setting ablation parameters, wherein the ablation parameters represent the degree of conformity of the first ablation volume and the tumor target TV region; at least one of the number of needle tracks, the position of the needle tracks, the power of the microwave radiation source and the operating time is modified and the first ablation volume is recalculated to meet the ablation parameters. The technical scheme provided by the invention simulates the treatment effect of the microwave ablation operation, provides reference for the implementation of doctors before the operation, and relieves the high dependence on personal experience of the doctors.)

1. A method of tumor ablation simulation, comprising:

marking a tumor target in a medical image, and establishing a three-dimensional image containing a TV region of the tumor target;

generating a needle distribution area enveloping a tumor target TV area in the three-dimensional image, arranging a plurality of needle paths in the needle distribution area, wherein the needle paths have no intersection point in the needle distribution area, and arranging a microwave radiation source in the needle paths, wherein the microwave radiation source generates an electromagnetic field to ablate the tumor target;

calculating a first ablation volume covered by the electromagnetic field;

setting ablation parameters, wherein the ablation parameters represent the degree of conformity of the first ablation volume with the tumor target TV region;

modifying at least one of the needle track number, needle track position, microwave radiation source power and operating time, and recalculating the first ablation volume to meet the ablation parameters.

2. The method of claim 1, wherein the step of generating a needle distribution region that envelops the tumor target TV region comprises:

setting a cuboid, wherein the cuboid envelops a tumor target TV region in a three-dimensional direction by a minimum volume;

removing the organs or bone tissue area at risk contained in the cuboid to form the needle distribution area.

3. The method of claim 1, wherein the step of calculating a first ablation volume covered by an electromagnetic field comprises:

calculating the electromagnetic field distribution of the microwave radioactive source;

calculating the temperature field of the tumor target according to the electromagnetic field distribution;

setting a temperature threshold, wherein the volume of the constant temperature surface envelope of the temperature threshold is a first ablation volume.

4. The method of claim 1, further comprising:

and optimizing three parameters of the needle path position, the power of the microwave radioactive source and the working time under the condition of meeting the ablation parameters by taking the minimum number of the needle paths and the minimum first ablation volume as optimization targets.

5. The method of claim 1, further comprising:

acquiring a medical image after tumor target ablation, acquiring a second ablation volume in the medical image after tumor target ablation, and calculating the conformal degree of the second ablation volume and a tumor target TV region.

6. A tumor ablation simulation system, comprising:

the acquisition module is used for marking a tumor target in the medical image and establishing a three-dimensional image containing a TV region of the tumor target;

the planning module is used for generating a needle distribution area enveloping a tumor target TV area in the three-dimensional image, a plurality of needle channels are arranged in the needle distribution area, the needle channels have no intersection points in the needle distribution area, and microwave radioactive sources are arranged in the needle channels and generate electromagnetic fields to ablate the tumor target;

a calculation module for calculating a first ablation volume covered by the electromagnetic field;

a parameter module for setting ablation parameters characterizing a degree of conformity of the first ablation volume with a tumor target TV region;

an optimization module for modifying at least one of the needle track number, needle track position, microwave radiation source power and on-time, recalculating the first ablation volume to meet the ablation parameters.

7. The system of claim 6, wherein the step of generating a needle placement region that envelops a tumor target TV region in the planning module comprises:

setting a cuboid, wherein the cuboid envelops a tumor target TV region in a three-dimensional direction by a minimum volume;

removing the organs or bone tissue area at risk contained in the cuboid to form the needle distribution area.

8. The system of claim 6, wherein the computing module is further configured to:

calculating the electromagnetic field distribution of the microwave radioactive source;

calculating the temperature field of the tumor target according to the electromagnetic field distribution;

setting a temperature threshold, wherein the volume of the constant temperature surface envelope of the temperature threshold is a first ablation volume.

9. The system of claim 6, wherein the optimization module is further configured to:

and optimizing three parameters of the needle path position, the power of the microwave radioactive source and the working time under the condition of meeting the ablation parameters by taking the minimum number of the needle paths and the minimum first ablation volume as optimization targets.

10. The system of claim 6, further comprising:

the verification module is used for acquiring a medical image after tumor target ablation, acquiring a second ablation volume in the medical image after tumor target ablation, and calculating the degree of conformity between the second ablation volume and a tumor target TV region.

Technical Field

The invention relates to the technical field of virtual surgery, in particular to a tumor ablation simulation method and system.

Background

The microwave ablation is one kind of local heat ablation, and has the advantages of minimal invasion, less adverse reaction, determined curative effect, high heat efficiency, less influence of carbonized tissue and blood flow, wide ablation range, etc. In recent years, image-guided microwave ablation technology has been widely applied to the treatment of various solid tumors, especially in the treatment of liver cancer and lung cancer. At present, the microwave ablation operation at home and abroad still does not establish a mature industrial standard at present, doctors lack technical means to plan and simulate the operation before the microwave ablation operation, and doctors have personal experience in severe operation, so that the operation effect varies from person to person.

Disclosure of Invention

In view of this, the present invention provides a tumor ablation simulation method and system to alleviate the deficiencies of the prior art.

According to some embodiments, in a first aspect the invention provides a tumour ablation simulation method comprising: marking a tumor target in the medical image, and establishing a three-dimensional image containing a tumor target TV region; generating a needle distribution area enveloping a tumor target TV area in a three-dimensional image, arranging a plurality of needle ways in the needle distribution area, wherein the needle ways have no intersection points in the needle distribution area, arranging a microwave radioactive source in each needle way, and generating an electromagnetic field by the microwave radioactive source to ablate a tumor target; calculating a first ablation volume covered by an electromagnetic field; setting ablation parameters, wherein the ablation parameters represent the degree of conformity of the first ablation volume and the tumor target TV region; at least one of the number of needle tracks, the position of the needle tracks, the power of the microwave radiation source and the operating time is modified and the first ablation volume is recalculated to meet the ablation parameters.

According to some embodiments, in a second aspect the invention provides a tumor ablation simulation system comprising: the acquisition module is used for marking a tumor target in the medical image and establishing a three-dimensional image containing a tumor target TV region; the planning module is used for generating a needle distribution area enveloping a tumor target TV area in a three-dimensional image, a plurality of needle paths are arranged in the needle distribution area, the needle paths do not have intersection points in the needle distribution area, and microwave radioactive sources are arranged in the needle paths and generate electromagnetic fields to ablate tumor targets; a calculation module for calculating a first ablation volume covered by an electromagnetic field; a parameter module for setting ablation parameters, the ablation parameters characterizing a degree of conformity of the first ablation volume with the tumor target TV region; an optimization module for modifying at least one of the number of needle tracks, the needle track position, the microwave radiation source power and the operating time, and recalculating the first ablation volume to meet the ablation parameters.

The invention has the following beneficial effects:

the technical scheme provided by the invention can have the following beneficial effects: the tumor ablation simulation method and the system are provided, the treatment effect of the microwave ablation operation is simulated, reference is provided for doctors to implement before the operation, and high dependence on personal experience of the doctors is relieved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are one embodiment of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic flow chart of a tumor ablation simulation method according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of a tumor ablation simulation system according to a second embodiment of the present invention.

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and the described embodiments are some, but not all embodiments of the present invention.

The first embodiment:

fig. 1 is a schematic flow chart of a tumor ablation simulation method according to a first embodiment of the present invention, as shown in fig. 1, the method includes the following 5 steps.

Step S10: and establishing a three-dimensional image containing the tumor target TV region. Specifically, a tumor target is marked in the medical image, and a three-dimensional image containing a TV region of the tumor target is established.

In an alternative embodiment, the tumor target in the medical image is detected based on a time domain or frequency domain feature of the tumor target, i.e. the tumor target is detected by a color and frequency feature of the tumor target. Or marking the tumor target in the medical image in a manual drawing mode.

It should be noted that the TV (Target volume) treatment Target area is a CTV (clinical Target volume) clinical Target area, which includes the Tumor and the potentially invaded tissue that are determined to exist, the gtv (gtv) Tumor area and the surrounding subclinical lesion constitute the CTV, and the microwave ablation treatment aims to cause the high-speed rotational motion of the surrounding water molecules by the microwave radiation field to increase the temperature by friction, so as to solidify, dehydrate and necrose the human tissue in the Tumor TV area. The medical image may be a CT (Computed Tomography) image or an MRI (Magnetic Resonance Imaging) image.

Step S11: and setting a tumor ablation simulation area. Specifically, a needle distribution area enveloping a tumor target TV area is generated in the three-dimensional image, a plurality of needle channels are arranged in the needle distribution area, the needle channels do not have intersection points in the needle distribution area, and microwave radioactive sources are arranged in the needle channels and generate electromagnetic fields to ablate the tumor target.

In an alternative embodiment, the step of generating a needle distribution region that envelops the tumor target TV region comprises: setting a cuboid, wherein the cuboid envelops a tumor target TV region in a three-dimensional direction by a minimum volume; the region of the organ or bone tissue at risk contained by the cuboid is removed to form a needle distribution region. It should be noted that the cube encloses the tumor target TV region in three dimensions with a minimum volume, i.e. the tumor target TV region is entirely within the cuboid, and if the cube is reduced in volume, there will be tumor target TV regions outside the cuboid, i.e. each face of the cuboid is tangent to the tumor target TV region.

Step S12: a first ablation volume covered by the electromagnetic field is calculated.

It should be noted that the electromagnetic field generated by the plurality of needle tracks radiates the electromagnetic field to the periphery with the microwave radiation source as the center, and the intensity of the electromagnetic field is gradually reduced as the distance from the microwave radiation source is increased. Optionally, a first ablation volume covered by the electromagnetic field is calculated based on the power and on-time of the microwave source. Illustratively, the distribution of the electromagnetic field can be obtained in public literature or commercial software, depending on the power and operating time of the microwave source.

In an alternative embodiment, firstly, the electromagnetic field distribution of the microwave radiation source is calculated, and then the temperature field of the tumor target is calculated according to the electromagnetic field distribution; and setting a temperature threshold, wherein the volume of the envelope of the constant temperature surface is the first ablation volume. For example, setting the temperature threshold to 60 degrees celsius, at the secondary temperature, tissue in the target TV region of the tumor will coagulate, dehydrate and necrose.

Step S13: and setting ablation parameters. The ablation parameter characterizes how well the first ablation volume conforms to the tumor target TV region. By counting the overlapping portions of the first ablation volume and the tumor target TV region, as well as the non-overlapping portions, the degree of conformity between the two can be derived.

Illustratively, the ablation parameters include a conformal index, a coverage rate, an over-ablation rate, and an under-ablation rate. E.g. a first ablation volume of V₁Tumor target TV region volume is V_tThe volume of the coinciding part of the first ablation volume and the tumor target TV region is V_1t

Conformal index: the first ablation volume corresponds to the shape and size of the tumor target TV region.

Coverage rate: v_1tAs a percentage of Vt.

Over-ablation rate: the first ablation volume comprises a normal tissue volume as a percentage of the first ablation volume.

Non-ablation rate: the first ablation volume does not contain a percentage of the tumor target TV region volume as a tumor target TV region volume.

Step S14: and optimizing the microwave ablation simulation parameters. Specifically, at least one of the number of needle tracks, the position of the needle tracks, the power of the microwave radiation source and the operating time is modified and the first ablation volume is recalculated to meet the ablation parameters. In order to meet the ablation parameters, four parameters of needle path number, needle path position, microwave radioactive source power and working time are adjusted.

In an alternative embodiment, the three parameters of needle track position, microwave radiation source power and working time are optimized under the condition of meeting the ablation parameters by taking the minimum needle track number and the minimum first ablation volume as optimization targets. Illustratively, the needle track number, the first ablation volume are used as optimization targets, the ablation parameters are used as constraints, the needle track position, the power of the microwave radiation source and the working time are used as optimization variables, and values of the needle track position, the power of the microwave radiation source and the working time under the condition that the needle track number is minimum and the first ablation volume is minimum are solved by using a multi-objective optimization method.

In some embodiments, after the ablation procedure is completed, a post-ablation medical image of the tumor target is acquired, a second ablation volume is acquired in the post-ablation medical image of the tumor target, and the degree of conformity of the second ablation volume with the TV region of the tumor target is calculated. Thereby verifying the accuracy of the tumor ablation simulation method of the embodiment.

Illustratively, the ablation parameters include a conformal index, a coverage rate, an over-ablation rate, and an under-ablation rate. E.g. a second ablation volume of V₂Tumor target TV region volume is V_tThe volume of the coinciding part of the first ablation volume and the tumor target TV region is V_2t

Conformal index: the second ablation volume corresponds to the tumor target TV region in shape and size.

Coverage rate: v_2tAccount for V_tPercentage of (c).

Over-ablation rate: the second ablation volume comprises a normal tissue volume as a percentage of the first ablation volume.

Non-ablation rate: the second ablation volume does not contain a percentage of the tumor target TV region volume as a tumor target TV region volume.

Second embodiment:

fig. 2 is a schematic structural diagram of a tumor ablation simulation system according to an embodiment of the present invention, and as shown in fig. 2, the tumor ablation simulation system 100 includes:

an acquisition module 101 for marking a tumor target in a medical image, creating a three-dimensional image containing a TV region of the tumor target.

And the planning module 102 is used for generating a needle distribution area enveloping the tumor target TV area in the three-dimensional image, arranging a plurality of needle paths in the needle distribution area, wherein the needle paths have no intersection point in the needle distribution area, and arranging a microwave radiation source in each needle path, wherein the microwave radiation source generates an electromagnetic field to ablate the tumor target.

A calculation module 103 for calculating a first ablation volume covered by an electromagnetic field.

A parameter module 104 for setting ablation parameters, the ablation parameters characterizing a degree of conformity of the first ablation volume with the tumor target TV region.

An optimization module 105 for modifying at least one of the number of needle tracks, the needle track position, the microwave radiation source power and the operating time to recalculate the first ablation volume to meet the ablation parameters.

In some embodiments, the step of generating a needle placement region enveloping the tumor target TV region in the planning module 102 comprises: setting a cuboid, wherein the cuboid envelops a tumor target TV region in a three-dimensional direction by a minimum volume; the region of the organ or bone tissue at risk contained by the cuboid is removed to form a needle distribution region.

In some embodiments, the calculation module 103 is further configured to: calculating the electromagnetic field distribution of the microwave radioactive source; calculating the temperature field of the tumor target according to the electromagnetic field distribution; and setting a temperature threshold, wherein the volume of the envelope of the constant temperature surface is the first ablation volume.

In some embodiments, the optimization module 105 is further configured to: the minimum needle track number and the minimum first ablation volume are taken as optimization targets, and under the condition that ablation parameters are met, three parameters of needle track positions, microwave radioactive source power and working time are optimized.

In some embodiments, the tumor ablation simulation system 100 further comprises: and the verification module is used for acquiring the medical image after the tumor target is ablated, acquiring a second ablation volume in the medical image after the tumor target is ablated, and calculating the conformal degree of the second ablation volume and the tumor target TV region.

Finally, it should be noted that: the above-mentioned embodiments are only specific embodiments of the present invention, which are used for illustrating the technical solutions of the present invention and not for limiting the same, and the protection scope of the present invention is not limited thereto, although the present invention is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.