CN113082549B

CN113082549B - Particle beam monitoring method and particle beam therapy device

Info

Publication number: CN113082549B
Application number: CN202110327764.1A
Authority: CN
Inventors: 赵鹏; 许嘉
Original assignee: China Israel Kanglian Weifang Particle Beam Industrial Technology Research Institute Co ltd; China Israel Kanglian International Medical Technology Co ltd
Current assignee: China Israel Kanglian Weifang Particle Beam Industrial Technology Research Institute Co ltd; China Israel Kanglian International Medical Technology Co ltd
Priority date: 2021-03-26
Filing date: 2021-03-26
Publication date: 2022-12-06
Anticipated expiration: 2041-03-26
Also published as: CN113082549A

Abstract

The present disclosure relates to the technical field of tumor radiotherapy,in particular, a particle beam monitoring method and a particle beam therapy apparatus are provided. The method comprises the following steps: the method comprises the following steps: the position point coordinate when the particle beam passes through the detector is set as (X) ₀ ，Y ₀ ) (ii) a The actual position point coordinate of the particle beam as it passes through the detector is (X) ₁ ，Y ₁ ) Distance P between actual position point and set position point ₁ (ii) a The length of the telescopic channel is changed, and the actual position coordinate of the particle beam when the particle beam passes through the detector is (X) _N ，Y _N ) (ii) a The controller is based on (X) _N ，Y _N ) The value of (a) is the coordinate (X) of the particle beam at which the detector should indicate when the telescopic channel is not extended or at some set extension length as described above _N ’，Y _N ') to obtain a distance P between the actual position point and the set position point of the particle beam in the same plane _N The controller is based on P _N The change of the value of the signal sends out a corresponding working signal. The treatment device includes a particle delivery channel, a detector, a reservoir, and a controller.

Description

Particle beam monitoring method and particle beam therapy device

Technical Field

The present disclosure relates to the field of tumor radiotherapy, and in particular, to a particle beam monitoring method and a particle beam therapy apparatus.

Background

Teletherapy is defined as a therapeutic method in which a radiation source is at a distance from the body to be treated. X-rays and electron beams have long been used for teletherapy to treat various cancers. However, the linear energy transfer of the X-rays approaches an exponential decay function, and thus safety is not improved for increased exposure depth. Heavy particles are widely used in teletherapy, where hadrons or protons have gained increasing acceptance, due to their ability to irradiate to a specific depth without significantly damaging intervening tissue.

Protons or ions can be focused to a target region at a certain depth, and therefore, the dose distribution can be matched with the target region with high accuracy. In order to ensure complete irradiation of the target area, a plurality of light beams reaching the target area from a plurality of different directions of the living body (patient) are preferred. The point at which the multiple beams intersect (whether sequential or simultaneous) is referred to as the isocenter, and in order to maximize the biological effect, the isocenter coincides with the location point of the target region, which may be a certain point in the target region, preferably a point in the central region or the target region center point.

In the first phase of treatment, the target area is imaged and a treatment plan is developed that includes dose, patient position, and angle of irradiation, among other things. Furthermore, the beam direction during the subsequent irradiation is ensured according to the patient's label. The irradiation is then performed in a plurality of treatment phases over a period of time in response to the developed treatment plan. In addition, in order to reduce the propagation path of the particle beam in the air, the transportation channel of the particle beam therapy apparatus is usually arranged in a telescopic manner, that is, the transportation channel includes a first pipeline and a telescopic channel which are communicated with each other, a driving device is connected to the telescopic channel, and the telescopic channel is driven by the driving device to be telescopic along the length direction thereof, so as to change the length of the particle beam passing through the air section, and avoid the phenomenon that the particle beam deviates from the irradiation point due to the longer propagation path of the particle beam in the air.

Although the particle beam is controlled to irradiate according to the treatment plan, the beam should be monitored to avoid safety accidents caused by irradiation deviation of the particle beam. In a conventional particle beam monitoring method, a detection device detects the position of a particle beam, and when the particle beam deviates from a threshold value, a controller feeds back to turn off the beam source or adjust the position of the particle beam.

Disclosure of Invention

To solve the above technical problem or to at least partially solve the above technical problem, the present disclosure provides a particle beam monitoring method and a particle beam therapy apparatus.

The present disclosure provides a particle beam monitoring method comprising the steps of:

arranging the detector at the particle beamThe end of the telescopic channel of the beam treatment device, when the telescopic channel is not extended or at a certain set extension length, sets the position point coordinate of the particle beam when passing through the detector as (X) ₀ ，Y ₀ )；

The actual position point coordinate when the detector detects the particle beam passing through the detector is (X) ₁ ，Y ₁ ) From the coordinates (X) of the actual location point ₁ ，Y ₁ ) Coordinates (X) with set position point ₀ ，Y ₀ ) Obtaining the distance P between the actual position point and the set position point ₁ ；

If the length of the telescopic channel changes when the Nth particle beam passes through the detector, the actual position coordinate when the detector detects that the particle beam passes through the detector is (X) _N ，Y _N )；

The controller is based on (X) _N ，Y _N ) Is not extended or is extended to a certain set length, at which angle the detector should indicate the coordinates (X) of the particle beam _N ’，Y _N ') and further obtaining a distance P between the actual position point and the set position point of the particle beam in the same plane _N The controller is based on P _N The change of the value of the signal sends out a corresponding working signal.

Optionally, when the telescopic channel is not extended or at a certain set extension length, the vertical distance between the initial position of the particle beam and the detector is N ₁ The coordinates (X) of the particle beam that the detector should indicate _N ’，Y _N ') includes: x _N ’＝X _N ×N ₁ /N _N ’，Y _N ’＝Y _N ×N ₁ /N _N ’，N _N ' is the length variation N of the telescopic channel _N The vertical distance between the initial position of the particle beam and the detector.

Optionally, when the length of the telescopic channel changes by N _N The controller then feeds back the actual position coordinate of the particle beam as (X) as it passes through the detector _N ，Y _N ) Obtaining an extension of the position of the particle beam as it passes through the detector and the initial direction of the particle beamPerpendicular distance L therebetween _N ，L _N ＝tanα _N ×N _N ', wherein, α _N Is the angle between the actual direction of irradiation of the particle beam and the initial direction of the particle beam, N _N ' is the length variation N of the telescopic channel _N Then the vertical distance between the initial position of the particle beam and the detector; controller according to alpha _N Is not extended or is extended to a certain set length, at which angle the detector should indicate the coordinates (X) of the particle beam _N ’，Y _N ’)。

Optionally, when the telescopic channel is not extended or has a certain set extension length, the angle between the irradiation direction of the particle beam and the initial direction of the particle beam set in the treatment plan is α, and the perpendicular distance between the position of the particle beam when passing through the detector and the extension line of the initial direction of the particle beam is L ₁ The vertical distance between the initial position of the particle beam and the detector is N ₁ (ii) a Length variation N of telescopic passage _N The vertical distance between the initial position of the particle beam and the detector is then N _N ’，N _N ’＝tanα/L ₁ +N _N 。

Optionally, the length change of the telescopic passage comprises an extension or a shortening of the telescopic passage, and when the telescopic passage is extended, N is _N Is a positive value, N when the telescopic passage is shortened _N The value of (b) is negative.

Optionally, when the telescopic channel is not extended or at a certain set extension length, the position coordinate (X) of the particle beam passing through the detector set in the treatment plan is determined ₀ ，Y ₀ ) And storing into a storage.

Optionally, when the controller detects P _N The controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam when the value of (a) gradually increases or increases in a jump.

Optionally, a plurality of continuous position points when the detector detects that the particle beam passes through the detector are taken as a group, an average value of distances between a plurality of actual position points and a set position point in the same plane in each group is obtained, and when the detector detects that the average value of the distances between the actual position points and the set position points of the particle beam gradually increases or increases in a jumping manner, the controller turns off the particle beam, or controls the deflection magnet to adjust a deflection angle of the particle beam.

Optionally, the position of the particle beam when passing through the detector set in the treatment plan is a position point of the particle beam when passing through the detector and a first region around the position point, when the detector detects that the particle beam is in the first region, the particle beam is fed back to be normal, and when the detector detects that the position of the particle beam is outside the first region, the particle beam is signaled to deviate from the set position.

Optionally, when the telescopic channel is not extended or at a certain set extension length, the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam when the distance between the point at which the controller detects that the particle beam passes through the detector and the set point gradually increases or increases in a jumping manner.

The present disclosure also provides a particle beam monitoring method, comprising the steps of:

setting the detector at the end of the telescopic channel of the particle beam treatment device, and setting the angle between the irradiation direction of the particle beam and the initial direction of the particle beam in a treatment plan to be alpha when the telescopic channel is not extended or is at a certain set extension length;

if the length of the telescopic channel changes when the Nth particle beam passes through the detector, the actual position coordinate when the detector detects that the particle beam passes through the detector is (X) _N ，Y _N ) Further, an included angle alpha between the actual irradiation direction of the particle beam and the initial direction of the particle beam is obtained _N The controller is based on _N The change of the value of (b) gives out a corresponding working signal.

Optionally, the controller turns off the particle beam when the angle between the actual particle beam and the set particle beam detected by the detector gradually increases or increases abruptly, or controls the deflection magnet to adjust the deflection angle of the particle beam.

Optionally, while stretchingAfter the length of the contraction channel is changed, the controller feeds the actual position coordinate (X) of the particle beam passing through the detector according to the feedback of the detector _N ，Y _N ) The vertical distance between the initial position of the particle beam and the detector is N _N ' the angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam is alpha _N A perpendicular distance L between the position of the particle beam when passing through the detector and an extension of the initial direction of the particle beam _N ，L _N ＝tanα _N ×N _N ', further give α _N The value of (c).

Optionally, the length change of the telescopic passage comprises an extension or a shortening of the telescopic passage, and when the telescopic passage is extended, N is _N The value of (A) is a positive value, N is a positive value when the telescopic passage is shortened _N The value of (b) is a negative value.

The present disclosure also provides a particle beam therapy apparatus, including a therapy apparatus body, the therapy apparatus body is provided with:

the particle conveying channel comprises a first pipeline and a telescopic channel which are mutually communicated, a driving device is connected to the telescopic channel, the telescopic channel is driven by the driving device to stretch along the length direction of the telescopic channel, and particle beams sequentially penetrate through the first pipeline and the telescopic channel and then irradiate to a target area;

at least one detector arranged at one end of the telescopic channel far away from the first pipeline, wherein the detector is used for detecting the position information of the particle beam when the particle beam passes through the detector;

a storage for storing a set position of the particle beam when the telescopic channel is not extended or passes through the detector at a set extension length in a treatment plan;

and the controller obtains the position coordinates when the telescopic channel does not extend out or the particle beam passes through the detector when the particle beam passes through the detector according to the actual position fed back by the detector, so as to obtain the distance between the actual position point and the set position point in the same plane, and sends a corresponding working signal according to the change of the distance between the actual position point and the set position point, or sends a corresponding working signal according to the change of an included angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam.

Compared with the prior art, the technical scheme provided by the embodiment of the disclosure has the following advantages:

the detector is arranged at the end part of the telescopic channel of the particle conveying channel, the measured position of the particle beam is fed back to the controller in real time, after the telescopic channel is extended, the controller obtains the coordinate of the particle beam when the telescopic channel does not extend out or is extended to a certain set extension length according to the position point coordinate fed back by the detector, the deflection condition of the particle beam is further obtained in real time, the controller sends out a corresponding working instruction according to the deflection condition of the particle beam, the controller is ensured to adjust the emission state of the particle beam in time, critical adjustment is avoided, and the safety of a patient is ensured.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present disclosure, the drawings used in the embodiments or technical solutions in the prior art description will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic structural diagram of a particle transport channel according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a particle transport passageway with a telescoping passageway in an extended state according to an embodiment of the disclosure;

FIG. 3 is a schematic view of the telescoping passages in a collapsed state and in an extended state according to embodiments of the disclosure;

FIG. 4 is a schematic view of a particle beam as it passes through a detector according to an embodiment of the disclosure;

FIG. 5 is a schematic diagram illustrating a particle beam as it is positioned further away from a set position according to an embodiment of the present disclosure;

fig. 6 is a schematic diagram illustrating a position of a particle beam gradually separated from a predetermined position along a horizontal direction according to an embodiment of the disclosure;

FIG. 7 is a schematic diagram illustrating a discrete distribution of particle beam positions according to an embodiment of the disclosure;

FIG. 8 is a diagram illustrating an embodiment of the present disclosure in which the distance between the position of the particle beam and the set position increases abruptly;

fig. 9 is a schematic diagram illustrating a case where a distance between a position of a particle beam and a set position is constant according to an embodiment of the disclosure;

fig. 10 is a schematic diagram of a position of a particle beam that should be indicated by a detector after a length of a particle expansion channel is changed according to an embodiment of the present disclosure.

10, a particle conveying channel; 11. a first conduit; 12. a telescopic channel; 20. a detector; 30. an X-axis scanning magnet; 40. a Y-axis scanning magnet; a. initial position of the particle beam.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, aspects of the present disclosure will be further described below. It should be noted that the embodiments and features of the embodiments of the present disclosure may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced in other ways than those described herein; it is to be understood that the embodiments disclosed in the specification are only a few embodiments of the present disclosure, and not all embodiments.

Example 1

The particle beam monitoring method provided by the embodiment of the application comprises the following steps:

step S1, as shown in fig. 1 to 3, the detector 20 is disposed at the end of the telescopic channel 12 of the particle beam therapy apparatus, and when the telescopic channel 12 is not extended or at a certain set extension length, the coordinate of the position point when the particle beam passes through the detector 20 is set as (X) ₀ ，Y ₀ ). As shown in fig. 4, since the particle beam has a certain diameter, the center point of the particle beam when the particle beam passes through the detector 20 is preferably used as the position point detected by the detector 20.

In some embodiments, detector 20 may be a light detector. The light detector includes a light detector body and an illumination material arranged to emit light in response to the particle beam, the light detector body for detecting a position of the particle beam on the illumination material. When the particle beam passes through the illumination material, light is emitted at the position where the illumination material is passed through by the particle beam, and the light-emitting position is obtained by the light detector body and fed back to the controller. The illumination material includes a scintillator that emits light in response to particle radiation. Further, the photodetector body includes a photosensor by which light on the illumination material is converted into an electrical signal. Wherein the spatial position of the emitted light may be determined as the center of the particle beam or as the portion of the illumination material exhibiting the maximum emitted light intensity or the center thereof, the spatial position being the detected beam position point. Depending on the measurement accuracy requirements, it is preferred that the center point of the particle beam is the center point of the illumination material exhibiting the maximum emitted light intensity.

In other embodiments, detector 20 includes an ionization chamber comprising a plurality of ionization chamber bodies, each ionization chamber body having an anode and a cathode, and an ionization detector, the power supply providing power to the anode and cathode. The particle beam ionizes a gas within the ionization chamber bodies, a cathode and an anode connected on each ionization chamber body are coupled to an ionization detector arranged to detect a current level output by each ionization chamber body. In one embodiment, the position of the ionization chamber body with the largest output current or the central position of a plurality of ionization chamber bodies with the largest output current is determined as the center point of the particle beam; in other embodiments, the ionization chamber body with the significantly smaller current is determined as the edge of the particle beam and the ionization chamber body with the significantly larger current is determined as the middle region of the particle beam according to the identified magnitude of the current intensity, so as to determine the profile of the particle beam and determine the center of the profile as the center of the particle beam. Preferably, a profile of the particle beam is fitted to the responsive ionization chamber, with the center of the profile being determined as the center point of the detected particle beam.

In other embodiments, detector 20 comprises a segmented ionization chamber, and the center point of the beam profile, the point of maximum beam dose, or the center point of the profile of the region of maximum beam dose is determined as the center point of the particle beam based on the detected beam profile or beam dose distribution.

The position of the particle beam when passing through the detector 20 set in the treatment plan is the position point of the particle beam when passing through the detector 20 and the first region around the position point, when the detector 20 detects that the particle beam is in the first region, the particle beam is fed back to be normal, and when the detector 20 detects that the position of the particle beam is outside the first region, the particle beam is signaled to deviate from the set position. Specifically, the set position of the particle beam is a set position point when the particle beam passes through the detector 20, that is, a center point when the particle beam passes through the detector 20. Moreover, there may be a certain deviation between the actual position point and the set position point when the particle beam passes through the detector 20, and the particle beam within the deviation range can be determined as a normal beam, that is, a certain range taking the set position point as the center is a first region, and the first region is the set range when the particle beam passes through the detector 20 in the treatment plan. In case the probe 20 is telescopically movable, the extent of the first area varies accordingly depending on the extension and retraction of the probe 20.

The detector 20 is arranged along the radial direction of the particle transport path 10, ensuring the accuracy of the measurement results. The detector 20 is preferably arranged at the output end of the particle transport channel 10, so that the particle beam detected by the detector 20 directly exits the particle transport channel 10, and the measured position is ensured when the particle beam exits the particle transport channel 10, thereby avoiding the particle beam from being problematic when exiting the particle transport channel 10 and further ensuring the safe treatment of the patient.

When the telescopic channel 12 is not extended or at a certain set extension length, the position coordinate (X) of the particle beam passing through the detector 20 set in the treatment plan ₀ 、Y ₀ ) And storing into a storage. The position of the particle beam as it passes through the detector 20 in the treatment plan may be stored programmatically, or information about the position of the particle beam as it passes through the detector 20 may be determined in an external system and stored in memory.

Step S2, the actual position point coordinate when the detector 20 detects that the particle beam passes through the detector 20 is (X) ₁ ，Y ₁ ) From the coordinates (X) of the actual location point ₁ ，Y ₁ ) Coordinates (X) with set position point ₀ ，Y ₀ ) Obtaining the distance P between the actual position point and the set position point ₁ . Wherein, P ₁ Is the connecting line between two points, and the position coordinates of the two points are known, therefore, P can be obtained ₁ The value of (c). Wherein the content of the first and second substances,

specifically, when the telescopic channel 12 is not extended or at a certain set extension length, the controller detects that the distance between the position point of the particle beam passing through the detector 20 and the set position point is gradually increased or increased in a jumping manner, the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam, and simultaneously, the controller sends out an alarm signal, and the alarm signal generates an alarm indication on a user interface and is specifically output to an external monitoring system and/or a display by the communication module. When the detector 20 detects that the position of the particle beam does not have a tendency to deviate from the set position, the controller outputs no relevant signal, or outputs a signal that the position is acceptable, and the detector 20 continues the treatment and proceeds to step S3. The deviation of the position of the particle beam may be caused by vacuum leakage, failure of the deflection magnet, problems in the initial beam position, and the like. Wherein the detector 20 detects that the change of the position of the particle beam should be within the set value, and the detector 20 is used for detecting whether the particle beam has a tendency to deviate from the set position.

Step S3, as shown in fig. 3, if the nth particle beam passes through the detector 20, the length of the telescopic channel 12 changes, and the actual position coordinate of the particle beam passing through the detector 20 detected by the detector 20 is (X) _N ，Y _N ). Specifically, the change in length here means the extension or contraction of the length of the telescopic passage 12.

Step S4, as shown in FIG. 10, the controller is based on (X) _N ，Y _N ) Is not extended or is at some set extension length as described above, at which angle the detector 20 should indicate the coordinates (X) of the particle beam _N ’，Y _N ') and further obtaining a distance P between the actual position point and the set position point of the particle beam in the same plane _N The controller is based on P _N The change of the value of the signal sends out a corresponding working signal. Wherein the content of the first and second substances,

the coordinates (X) of the particle beam that the detector 20 should indicate _N ’，Y _N ') the coordinates of the particle beam that the detector 20 should detect when the telescoping channels 12 are not extended or at some set extended length.

In some embodiments, the vertical distance between the initial position a of the particle beam and the detector 20 is N when the telescopic channel 12 is not extended or at a certain set extension length ₁ ，N ₁ Can be derived from measurements. As shown in fig. 10, the detector 20 should indicate the coordinates (X) of the particle beam _N ’，Y _N ') includes: x _N ’＝X _N ×N ₁ /N _N ’，Y _N ’＝Y _N ×N ₁ /N _N ’，N _N ' is the length variation N of the telescopic passage 12 _N The vertical distance between the initial position a of the particle beam and the detector 20. Wherein N is ₁ 、X _N 、Y _N And N _N ' are known quantities or can be derived from measurements and calculations, and thus the coordinates (X) of the particle beam that detector 20 should indicate are obtained _N ’，Y _N '). Wherein, the initial position a of the particle beam is the intersection point of the reverse extension line of the deflected particle beam and the initial direction of the beam.

The initial direction of the particle beam is the irradiation direction when the deflection magnet is not deflected, and the angle alpha between the set irradiation direction of the particle beam and the initial direction of the particle beam is the irradiation direction of the particle beam after the deflection magnet is deflected. Referring to fig. 1 to 3, the deflection magnet includes an X-axis scanning magnet 30 and a Y-axis scanning magnet 40, and a magnetic field, specifically, forces in two directions perpendicular to an initial incident direction of the particle beam, are applied to the particle beam by the X-axis scanning magnet 30 and the Y-axis scanning magnet 40 to adjust an angle of the particle beam, that is, the initial direction of the particle beam is an irradiation direction when the deflection magnet is not deflected.

In other embodiments, when the length of telescoping passage 12 changes by N _N The controller then feeds back the actual position coordinate of the particle beam as (X) as it passes through the detector 20, based on the detector 20 _N ，Y _N ) The perpendicular distance L between the position of the particle beam when it passes through the detector 20 and the extension of the initial direction of the particle beam is obtained _N ，L _N ＝tanα _N ×N _N ', wherein, α _N Is the angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam, N _N ' is the length variation N of the telescopic passage 12 _N Then, the vertical distance between the initial position a of the particle beam and the detector 20, due to N _N The value of' can be measured or calculated, and thus alpha can be obtained according to the above formula _N The value of (c). Controller according to alpha _N Is such that the telescopic passage 12 is not extended or at some set extension length as mentioned above, at which angle the detector 20 should indicate the pelletsCoordinates (X) of the beamlets _N ’，Y _N '). In particular due to the deflection angle alpha of the particle beam _N It is known that the vertical distance between the initial position a of the particle beam and the detector 20 is N when the telescopic channel 12 is not extended or at some set extension length as described above ₁ This can be measured and hence the position coordinates of the particle beam as it passes through the detector 20 when the telescopic passage 12 is not extended or at some set extension length as described above.

Wherein, after the length of the telescopic channel 12 is changed, the vertical distance N between the initial position a of the particle beam and the detector 20 _N The value of (c) can be obtained by measurement or by a relational expression.

As shown in fig. 3, when the telescopic passage 12 is not extended or at a certain set extension length, the angle between the irradiation direction of the particle beam and the initial direction of the particle beam set in the treatment plan is α, and the perpendicular distance between the position at which the particle beam passes through the detector 20 and the extension line of the initial direction of the particle beam is L ₁ The vertical distance between the initial position a of the particle beam and the detector 20 is N ₁ (ii) a Length variation N of telescopic channel 12 _N The vertical distance between the initial position a of the particle beam and the detector 20 is then N _N ’，N _N ’＝tanα/L ₁ +N _N . Wherein, alpha and N _N Is a set value, L ₁ Can be derived from the set position coordinates of the particle beam as it passes through the detector 20, and thus N can be derived _N The value of. Notably, the change in length of telescoping passage 12 includes an extension or contraction of telescoping passage 12, N being the length of telescoping passage 12 when telescoping passage 12 is extended _N Is a positive value, N when the telescopic passage 12 is shortened _N The value of (b) is negative.

The detector 20 is arranged at the end part of the telescopic channel 12 of the particle conveying channel 10, the measured position of the particle beam is fed back to the controller in real time, after the telescopic channel 12 extends, the controller obtains the coordinates of the particle beam when the telescopic channel 12 does not extend out or the length of the telescopic channel is set according to the position point coordinates fed back by the detector 20, the deflection condition of the particle beam is obtained in real time, the controller sends out a corresponding working instruction according to the deflection condition of the particle beam, the controller is ensured to adjust the emission state of the particle beam in time, critical adjustment is avoided, and the safety of a patient is ensured.

In some embodiments, when the controller detects P _N The controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam as the value of (d) increases. Wherein the value of N is 2, 3, 4, 5 …. The controller detects P ₂ Is greater than the set range of the particle beam, and the value P obtained later ₃ ，P ₄ … is greater than the predetermined range, when P is greater than P ₃ ＞P ₂ ＞P ₁ In this case, it is explained that the distance between the actual position of the particle beam and the set position gradually increases, and the particle beam gradually deviates from the set position.

Specifically, during the treatment, at a certain time, the controller obtains the same plane, and when the distance between the position where the particle beam passes through the detector 20 and the set position is greater than the set value and the distances between the subsequent continuous positions and the set position gradually increase, the controller sends out corresponding working signals. Referring to fig. 5, 6 and 7, the set position of the particle beam on the detector 20 is S1, the controller obtains the actual positions S2, S3 and S4 to be indicated by the detector 20 in the plane, and the distances between S2 and S1, S3 and S1 and S4 and S1 are gradually increased, where the position of the particle beam indicated by the detector 20 may be discontinuous, that is, several detected positions are discrete. The controller obtains at least two continuous deviation positions, preferably 3-4 continuous deviation positions are obtained by the controller, and corresponding working signals are sent out. The number of the feedback positions is related to the distance of each deviation, namely, the distance between the position obtained by the controller and the set position is gradually increased, when the increased value is gradually increased, the deviation trend of the deviation of the particle beam is larger, at the moment, the controller sends a corresponding working signal after obtaining 2-3 deviation positions, otherwise, the controller sends a corresponding working signal after obtaining 2-3 deviation positions, at the moment, the controller can determine that the positions are gradually far away after the detector 20 detects 4-5 positions, and then sends a corresponding working signal. This detection mode may be used in combination with the detection modes in the other embodiments.

In other embodiments, when P is detected by the controller _N The controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam when the value of (d) increases in a jump. Wherein, the value of N is 2, 3, 4, 5 …. The controller detects P ₂ Is greater than the set range of the particle beam, and when P is greater than P ₁₀ ＞P ₅ ＞P ₁ The time is to say that the distance between the actual position of the particle beam and the set position is increased in a jumping manner, and the particle beam gradually deviates from the set position.

As shown in fig. 8, during the treatment, the detector 20 continuously feeds back the position of the particle beam when passing through the detector 20, and when the controller obtains the same plane, the particle beam deviates from the set range, but the obtained positions are all in the set range thereafter, the detector 20 continuously monitors the particle beam. When the distance between the position point fed back later and the set position point is larger than the largest one of the distances between the position point fed back earlier and the set position point, the particle beam has a tendency of deviating from the set position, and the controller sends a corresponding working signal, otherwise, the controller continuously compares the deviation degree of the fed back position point. Specifically, the set position of the particle beam on the detector 20 is S1, the controller obtains the actual positions of the particle beam deviated from the set position when passing through the detector 20 in the same plane as S2, S5 and S10, and the distance between S2 and S1, the distance between S5 and S1 and the distance between S10 and S1 gradually increase. As above, the deviation position obtained by the controller is at least two, and preferably, the controller sends out corresponding working signals when obtaining 3-4 actual position points deviating from the set range.

In other embodiments, the average of the distances between the actual position points and the set position points in each group in the same plane is obtained by grouping a plurality of consecutive position points when the detector 20 detects that the particle beam passes through the detector 20, and the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam when the detector 20 detects that the average of the distances between the actual position points and the set position points of the particle beam gradually increases or increases in a jumping manner. This detection mode may be used in combination with the detection modes in the other embodiments.

Specifically, the detector 20 feeds back the detected position information to the controller by using a group of 5-10 continuous position points of the particle beam passing through the detector 20 detected by the detector 20, and further obtains the distances P between a plurality of actual position points and the set position point in the same plane _N1 、P _N2 、P _N3 、P _N4 、P _N5 And an average of the distances is obtained. Wherein, when the average value of the distances is within the set range, it indicates that the particle beam in the group is normal. And when the average value of the distances is out of the set range, indicating that the particle beams in the group deviate from the set range, and when the average value of the distances between the actual position points and the set position points of the particle beams in each group is larger than the largest one of the average values of the distances between the actual position points and the set position points of the particle beams fed back in the prior art, the controller indicates that the particle beams have the tendency of deviating from the set range. Specifically, the average value of the distance between the actual position point of the particle beam and the set position point in the adjacent groups gradually increases, or the average value of the distance between the actual position point of the particle beam and the set position point in the adjacent groups increases in a jump manner, which indicates that the particle beam has a tendency to deviate from the set range. Wherein the jump-up is described above and therefore not described herein too much. This detection method can exclude a position point detected by the probe 20 from deviating from the set range due to external factors. This detection mode may be used in combination with the detection modes in the other embodiments.

In other embodiments, as shown in fig. 9, when the controller obtains that the continuous particle beams all deviate from the set range, but the deviation value is unchanged or reduced, the controller sends out a normal beam signal or does not send out an operation signal. The set position of the particle beam on the detector 20 is S1, the actual positions of the particle beam when passing through the detector 20 are S2, S3 and S4, the distance between S2 and S1, the distance between S3 and S1 and the distance between S4 and S1 are constant.

Wherein, when the detector 20 detects that the position of the particle beam passing through the detector 20 has a tendency to deviate from the set position when the particle beam treatment apparatus is tested or a treatment plan is just started, the controller turns off the particle beam to overhaul the particle beam treatment apparatus. In a preferred embodiment, when the particle beam therapy apparatus is subjected to a deviation trend from the set position after the maintenance, the previous detection result is not used as a reference for comparison, and the recording is started with the distance between the first position point after the maintenance and the set position point as P1, that is, the position of the particle beam detected by the detector 20 is recorded again.

If the patient is in the treatment process, in order to avoid the waiting time of the patient caused by the machine being turned off being too long, the controller sends a command for adjusting the deflection angle of the particle beam towards the deflection magnet, so as to compensate the deflection angle of the particle beam, and the particle beam is in the set range.

It should be noted that the particle beams in the present disclosure do not deviate from the set threshold of the particle beam, and the deviation tendency is that the particle beams have a tendency to deviate from the threshold, that is, the particle beams are all within the threshold range. Specifically, the controller obtains that the distance between the actual position point and the set position point in the same plane does not exceed a threshold range of deviation distance, where the deviation trend is a trend that the particle beam has a threshold range, that is, the distances between the actual position point and the set position point of the particle beam are both within the threshold range of distance. If the detector 20 detects that the actual position point of the particle beam passing through the detector 20 exceeds the threshold range, the controller feeds back the position point information to the controller, and the controller sends out an instruction of closing the beam source to avoid the particle beam from damaging healthy tissues of a patient.

The probe 20 shown in fig. 4 to 9 is only a schematic diagram of the probe 20, and it does not mean that the probe 20 is circular, and the shape of the probe 20 may be designed according to the actual use requirement, such as circular, rectangular, or other irregular shapes.

Since the tumor has a certain volume, in one treatment plan, there are a plurality of positions on the tumor irradiated by the particle beam, so that the particle beam has a plurality of irradiation angles, i.e. there are a plurality of positions where the particle beam passes through the detector 20, and the particle beam irradiates different positions on the tumor, the above method is applicable, and the detection method can be used together with the detection method in other embodiments, i.e. the data detected by the detector 20 can be used together as a reference.

Example 2

The particle beam monitoring method provided by the present disclosure includes the following steps:

in step S1, as shown in fig. 3, the detector 20 is disposed at the end of the telescopic channel 12 of the particle beam therapy system, and when the telescopic channel 12 is not extended or is at a certain set extension length, the angle between the irradiation direction of the particle beam and the initial direction of the particle beam in the therapy plan is set to α. As described in embodiment 1, the initial direction of the particle beam is the irradiation direction when the deflection magnet is not deflected, and the angle α between the set irradiation direction of the particle beam and the initial direction of the particle beam is the irradiation direction of the particle beam after the deflection magnet is deflected.

If the length of the telescopic channel 12 changes when the nth particle beam passes through the detector 20, the actual position coordinate of the particle beam passing through the detector 20 detected by the detector 20 is (X) _N ，Y _N ) Further, an included angle alpha between the actual irradiation direction of the particle beam and the initial direction of the particle beam is obtained _N The controller is based on alpha _N The change of the value of the signal sends out a corresponding working signal.

Specifically, when the length of the telescopic channel 12 is changed, the controller feeds back the actual position coordinate of the particle beam passing through the detector 20 as (X) according to the detector 20 _N ，Y _N ) The vertical distance between the initial position a of the particle beam and the detector 20 is N _N ', actual irradiation direction of particle beam and particle beamThe angle between the initial directions is alpha _N The perpendicular distance between the position of the particle beam when passing through the detector 20 and the extension of the initial direction of the particle beam is L _N ，L _N ＝tanα _N ×N _N ', further give α _N The value of (c).

When the telescopic channel 12 is not extended or at a certain set extension length, the angle between the irradiation direction of the particle beam and the initial direction of the particle beam set in the treatment plan is α, and the perpendicular distance between the position of the particle beam when passing through the detector 20 and the extension line of the initial direction of the particle beam is L ₁ The vertical distance between the initial position a of the particle beam and the detector 20 is N ₁ (ii) a Length variation N of telescopic channel 12 _N The vertical distance between the initial position a of the particle beam and the detector 20 is then N _N ’，N _N ’＝tanα/L ₁ +N _N . The change in length of telescoping passage 12 includes an extension or contraction of telescoping passage 12, N, as telescoping passage 12 extends _N Is a positive value, N when the telescopic passage 12 is shortened _N The value of (b) is negative.

In some embodiments, the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam as the angle between the actual particle beam and the set particle beam detected by the detector 20 gradually increases or increases abruptly.

Specifically, the detector 20 feeds back the position of the passing particle beam to the controller, the controller obtains the actual routes of the particle beams according to the position fed back by the detector 20, and the controller sends out corresponding working signals when the detected actual routes of the plurality of particle beams gradually depart or jump away from the set route. The gradual and jump-away are described above, and therefore not described herein too much.

According to the particle beam deflection device, the detector 20 is arranged at the end part of the telescopic channel 12 of the particle conveying channel 10, the measured position of the particle beam is fed back to the controller in real time, the deflection condition of the particle beam is further obtained in real time, the controller sends out a corresponding working instruction according to the deflection condition of the particle beam, the controller is ensured to adjust the emission state of the particle beam in time, critical adjustment is avoided, and the safety of a patient is ensured.

The present disclosure also provides a particle beam therapy device, which comprises a therapy device body, wherein the therapy device body is provided with a particle delivery channel 10, a storage, a controller and at least one detector 20.

Referring to fig. 1, 2 and 3, the particle transport channel 10 includes a first tube 11 and a telescopic channel 12 which are communicated with each other, a driving device is connected to the telescopic channel 12, the telescopic channel 12 is driven by the driving device to extend and retract along the length direction thereof, and the particle beam sequentially passes through the first tube 11 and the telescopic channel 12 and then irradiates to the target region. The detector 20 is disposed at an end of the telescopic channel 12 far from the first pipe 11, the detector 20 is used for detecting position information when the particle beam passes through the detector 20, when the number of the detectors 20 is more than one, a plurality of the detectors 20 are arranged at intervals, but for saving cost, the detector 20 is preferably one. The memory is used to store the set position of the particle beam as it passes through the detector 20 when the telescopic channel 12 is not extended or at a set extension length during the treatment plan. The controller obtains the position coordinates when the telescopic channel 12 does not extend out or the particle beam passes through the detector 20 at a certain set extension length according to the actual position of the particle beam fed back by the detector 20 when the particle beam passes through the detector 20, and further obtains the distance between the actual position point and the set position point in the same plane, and the controller sends out corresponding working signals according to the change of the distance between the actual position point and the set position point, or sends out corresponding working signals according to the change of the included angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam. The therapeutic device body also comprises a particle accelerator which can be an accelerator capable of generating high-energy particle beams such as a synchrotron, a cyclotron, a synchrocyclotron, a linear accelerator and the like, wherein the particle beams can be high-energy particles such as protons, carbon ions, helium ions and the like. The synchrotron comprises a particle generator and a synchronous acceleration ring, wherein the output of the particle generator is coupled to the inlet of the synchronous acceleration ring, and the outlet of the synchronous acceleration ring is coupled to the inlet of the particle conveying pipeline. The particle beam monitoring method can be realized by the particle beam therapy device.

Specifically, the flexible duct 12 is made of a metal material such as stainless steel in a bellows shape or a bellows shape, and can isolate the external environment and withstand the vacuum state. The telescopic channel 12 is driven by the driving device to move along the length direction thereof, wherein the length direction is the arrow direction in fig. 1, 2 and 3. In some embodiments, the driving device is an electric push rod, specifically, an end plate may be disposed at an end of the bellows far away from the first pipeline 11, an edge of the end plate extends out of the bellows, a bottom plate is disposed at an outer periphery of the first pipeline 11, the electric push rod is disposed on the bottom plate, an output end of the electric push rod is connected with the end plate, the end plate is driven by the electric push rod to move along a length direction of the telescopic passage 12, and then the telescopic passage 12 is stretched. In other embodiments, the electric push rod can be replaced by a hydraulic or pneumatic cylinder. It can be seen that the driving manner of the telescopic channel 12 is not limited, and only needs to be satisfied that the telescopic channel 12 can be driven to be telescopic without affecting the irradiation of the particle beam, and the driving manner is common, and therefore, is not shown in the drawings.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present disclosure, which enable those skilled in the art to understand or practice the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of particle beam monitoring, comprising the steps of:

the detector (20) is arranged at the end of the telescopic channel (12) of the particle beam therapy device, and when the telescopic channel (12) is not extended or is at a certain set extension length, the position point coordinate of the particle beam passing through the detector (20) is set as (X) ₀ ，Y ₀ )；

The actual position point coordinate of the particle beam when the detector (20) detects the particle beam passing through the detector (20) is (X) ₁ ，Y ₁ ) From the coordinates (X) of the actual location point ₁ ，Y ₁ ) Coordinates (X) with set position point ₀ ，Y ₀ ) Obtaining the distance P between the actual position point and the set position point ₁ ；

If the length of the telescopic channel (12) changes when the Nth particle beam passes through the detector (20), the actual position coordinate when the detector (20) detects that the particle beam passes through the detector (20) is (X) _N ，Y _N )；

The controller is based on (X) _N ，Y _N ) Is such that the detector (20) is arranged to indicate the coordinates (X) of the particle beam at the angle at which the telescopic channel (12) is not extended or at the certain set extension length _N ’，Y _N ') and further obtaining a distance P between the actual position point and the set position point of the particle beam in the same plane _N The controller is based on P _N The change of the value of the signal is transmitted to a corresponding working signal;

when the controller detects P _N The controller turns off the particle beam when the value of (a) increases in a jump manner, or controls the deflection magnet to adjust the deflection angle of the particle beam,wherein, the value of N is 2, 3, 4, 5 ….

2. The particle beam monitoring method according to claim 1, wherein the vertical distance between the initial position (a) of the particle beam and the detector (20) is N when the telescopic channel (12) is not extended or at a certain set extension length ₁ The coordinates (X) of the particle beam that the detector (20) should indicate _N ’，Y _N ') includes: x _N ’＝X _N ×N ₁ /N _N ’，Y _N ’＝Y _N ×N ₁ /N _N ’，N _N ' is the length change N of the telescopic channel (12) _N Then the vertical distance between the initial position (a) of the particle beam and the detector (20).

3. A particle beam monitoring method according to claim 2, characterized in that N is the length of the telescopic channel (12) when it changes _N The controller then feeds back the actual position coordinates of the particle beam as (X) as it passes through the detector (20) based on the detector (20) _N ，Y _N ) Obtaining a perpendicular distance L between a position of the particle beam when passing through the detector (20) and an extension of the initial direction of the particle beam _N ，L _N ＝tanα _N ×N _N ', wherein, α _N Is the angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam, N _N ' is the length change N of the telescopic channel (12) _N Then the vertical distance between the initial position (a) of the particle beam and the detector (20); the controller is based on alpha _N Is such that the detector (20) is arranged to indicate the coordinates (X) of the particle beam at the angle at which the telescopic channel (12) is not extended or at the certain set extension length _N ’，Y _N ’)。

4. A particle beam monitoring method according to claim 2 or 3, characterized in that the angle between the irradiation direction of the particle beam and the initial direction of the particle beam as set in the treatment plan is determined when the telescopic channel (12) is not extended or at a certain set extension lengthAlpha, the perpendicular distance between the position of the particle beam when passing through the detector (20) and the extension of the initial direction of the particle beam is L ₁ The vertical distance between the initial position (a) of the particle beam and the detector (20) is N ₁ (ii) a Length variation N of telescopic passage (12) _N Then, the vertical distance between the initial position (a) of the particle beam and the detector (20) is N _N ’，N _N ’＝tanα/L ₁ +N _N 。

5. A particle beam monitoring method according to claim 4, wherein the change in length of the telescopic channel (12) comprises an elongation or a shortening of the telescopic channel (12), N being N when the telescopic channel (12) is elongated _N Has a positive value, N when the telescopic channel (12) is shortened _N The value of (b) is negative.

6. The particle beam monitoring method according to claim 1, characterized in that the position coordinates (X) of the particle beam as it is set in the treatment plan as it passes through the detector (20) when the telescopic channel (12) is not extended or at a certain set extension length ₀ ，Y ₀ ) And storing into a storage.

7. The particle beam monitoring method according to claim 1, wherein the average of the distances between the plurality of actual position points and the set position point in each group in the same plane is obtained by grouping a plurality of consecutive position points when the detector (20) detects that the particle beam passes through the detector (20), and the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam when the detector (20) detects that the average of the distances between the actual position points and the set position points of the particle beam gradually increases or increases in a jumping manner.

8. The particle beam monitoring method according to claim 1, wherein the position of the particle beam when passing through the detector (20) set in the treatment plan is a position point of the particle beam when passing through the detector (20) and a first region around the position point, the particle beam is fed back to be normal when the detector (20) detects that the particle beam is within the first region, and the particle beam is signaled to deviate from the set position when the detector (20) detects that the position of the particle beam is outside the first region.

9. The particle beam monitoring method according to claim 1, wherein the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam when the controller detects that the distance between the point at which the particle beam passes through the detector (20) and the set point gradually increases or increases in a jump when the telescopic channel (12) is not extended or at a certain set extension length.

10. A method of particle beam monitoring, comprising the steps of:

arranging a detector (20) at the end of a telescopic channel (12) of the particle beam treatment device, and setting the angle between the irradiation direction of the particle beam and the initial direction of the particle beam in a treatment plan to be alpha when the telescopic channel (12) is not extended or is at a certain set extension length;

if the length of the telescopic channel (12) changes when the Nth particle beam passes through the detector (20), the actual position coordinate when the detector (20) detects that the particle beam passes through the detector (20) is (X) _N ，Y _N ) Further, an included angle alpha between the actual irradiation direction of the particle beam and the initial direction of the particle beam is obtained _N The controller is based on alpha _N The change of the value of the signal is transmitted to a corresponding working signal;

when the angle between the actual particle beam and the set particle beam detected by the detector (20) gradually increases or increases in a jumping manner, the controller turns off the particle beam or controls the deflection magnet to adjust the deflection angle of the particle beam.

11. A particle beam monitoring method according to claim 10, wherein the controller feeds back the actual position coordinates of the particle beam as it passes through the detector (20) from the detector (20) after the length of the telescopic channel (12) has changedIs (X) _N ，Y _N ) The vertical distance between the initial position (a) of the particle beam and the detector (20) is N _N ' the angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam is alpha _N The perpendicular distance between the position of the particle beam when passing through the detector (20) and the extension of the initial direction of the particle beam is L _N ，L _N ＝tanα _N ×N _N ', further give α _N The value of (c).

12. A particle beam monitoring method according to claim 11, characterized in that when the telescopic channel (12) is not extended or at a certain set extension length, the angle between the irradiation direction of the particle beam and the initial direction of the particle beam set in the treatment plan is α, and the perpendicular distance between the position of the particle beam when passing through the detector (20) and the extension of the initial direction of the particle beam is L ₁ The vertical distance between the initial position (a) of the particle beam and the detector (20) is N ₁ (ii) a Length variation N of telescopic passage (12) _N Then, the vertical distance between the initial position (a) of the particle beam and the detector (20) is N _N ’，N _N ’＝tanα/L ₁ +N _N 。

13. A particle beam monitoring method according to claim 12, wherein the change in length of the telescopic channel (12) comprises an elongation or a contraction of the telescopic channel (12), N being N when the telescopic channel (12) is elongated _N Has a positive value, N when the telescopic channel (12) is shortened _N The value of (b) is negative.

14. A particle beam therapy device is characterized by comprising a therapy device body, wherein the therapy device body is provided with:

the particle conveying channel (10) comprises a first pipeline (11) and a telescopic channel (12) which are communicated with each other, a driving device is connected to the telescopic channel (12), the telescopic channel (12) is driven to stretch and retract along the length direction of the telescopic channel through the driving device, and particle beams sequentially penetrate through the first pipeline (11) and the telescopic channel (12) and then irradiate a target area;

at least one detector (20) arranged at an end of the telescopic channel (12) remote from the first pipe (11), the detector (20) being used for detecting position information of the particle beam when passing through the detector (20);

a storage for storing a set position of the particle beam when the telescopic channel (12) is not extended or passes through the detector (20) at a set extension length in a treatment plan;

and the controller obtains the position coordinates when the telescopic channel (12) does not extend or the particle beam passes through the detector (20) in a certain set extension length according to the actual position of the particle beam fed back by the detector (20) when passing through the detector (20) so as to obtain the distance between the actual position point and the set position point in the same plane, and sends out corresponding working signals according to the change of the distance between the actual position point and the set position point, or sends out corresponding working signals according to the change of the included angle between the actual irradiation direction of the particle beam and the initial direction of the particle beam.