CN215309765U - Treatment head and radiotherapy equipment - Google Patents

Abstract

The utility model discloses a treatment head and radiotherapy equipment, and belongs to the field of medical equipment. The treatment head comprises: a radiation source, a pre-collimator and a multi-leaf collimator; the pre-collimator and the multi-leaf collimator are sequentially arranged on a path of the ray beam emitted by the radiation source, the pre-collimator is configured to perform preliminary conformation on the ray beam emitted by the radiation source, and the multi-leaf collimator is configured to perform final conformation on the preliminarily conformed ray beam; a multi-leaf collimator comprising: a plurality of blade sets arranged side by side; each blade group includes: the first blade and the second blade are oppositely arranged; the first leaf and the second leaf each move in a direction parallel to an axis of a gantry of the radiation therapy system. No matter the treatment head rotates to any position along with the frame, the opening and closing directions of the blades are always parallel to the axis direction of the frame, so that the influence of gravity on the opening and closing of the blades is effectively avoided, and the accuracy of the multi-blade collimator in adapting to the ray beam is improved.

Description

Treatment head and radiotherapy equipment

Technical Field

The utility model relates to the field of medical equipment, in particular to a treatment head and radiotherapy equipment.

Background

A radiation therapy system is a medical device for treating tumors with radiation, and generally comprises: frame, treatment head, treatment bed, wherein, treatment bed is used for bearing the weight of the patient and removes the patient to assigned position department, and the treatment head sets up in the frame, utilizes the frame to drive the treatment head rotatory around the axis of isocenter, and the treatment head is rotatory with a plurality of bundles of rays focus to patient's tumour target area to the realization is to the radiotherapy of tumour tissue.

In the related art, the treatment head is capable of rotating on its own axis, and the treatment head includes: the radiation field is matched with the tumor shape of a patient. The multi-blade collimator comprises a plurality of groups of blades which can be opened and closed along the radial direction of the frame.

In the process of implementing the utility model, the inventor finds that at least the following problems exist in the related art:

according to the treatment head provided by the related art, the blades are opened and closed along the radial direction of the rack, and when the multi-blade collimator rotates to the side part of the rack, the opening and closing directions of the blades of the multi-blade collimator are along the gravity direction of the multi-blade collimator, and the gravity can cause adverse effects on the movement of the blades.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention provides a treatment head and a radiotherapy apparatus, which can solve the above technical problems.

Specifically, the method comprises the following technical scheme:

in one aspect, a therapy head is provided, the therapy head comprising: a radiation source, a pre-collimator and a multi-leaf collimator;

the pre-collimator and the multi-leaf collimator are sequentially arranged on the path of the radiation beam emitted by the radiation source, the pre-collimator is configured to perform primary conformity on the radiation beam emitted by the radiation source, and the multi-leaf collimator is configured to perform final conformity on the primarily conformed radiation beam;

the multileaf collimator includes: a plurality of blade sets arranged side by side; each blade group includes: the first blade and the second blade are oppositely arranged;

the first vane and the second vane each move in a direction parallel to an axis of a gantry of a radiation therapy system.

In some possible implementations, the treatment head is configured to be non-rotatable about its own axis.

In some possible implementations, the multi-leaf collimator further includes:

a plurality of first drive mechanisms corresponding to the first blades one to one, and a plurality of second drive mechanisms corresponding to the second blades one to one;

the first driving mechanism is connected with the first blade and used for driving the first blade to move along the direction parallel to the axis of the rack;

the second driving mechanism is connected with the second blade and used for driving the second blade to move along the direction parallel to the axis of the rack.

In some possible implementations, the maximum movement distance of the first blade and the second blade is both 5cm to 15 cm;

and the first drive mechanism is configured to be able to stop the first blade at any position within a range of motion;

the second drive mechanism is configured to enable the second blade to stop at any position within a range of motion;

in some possible implementations, the length directions of the first and second leaves are both parallel to the axial direction of the gantry of the radiation therapy system;

the lengths of the first blade and the second blade are both 2.5cm-7.5 cm;

the heights of the first blade and the second blade are both 6cm-8 cm.

In some possible implementations, the opposing leading ends of the first and second blades are each provided in an arcuate configuration.

In some possible implementations, the pre-collimator includes: the pre-collimator comprises a pre-collimator body and a pre-collimating hole formed in the pre-collimator body;

the pre-collimation hole is a quadrangular frustum pyramid-shaped through hole, and penetrates through the first surface and the second surface of the pre-collimator body, wherein the first surface and the second surface are opposite.

In some possible implementations, the pre-collimation aperture projects a field at an isocenter of a radiation treatment system in the shape of a bar;

the length of the short side of the radiation field is 5-15 cm;

the length of the long edge of the radiation field is 30-50 cm;

wherein the short side direction of the radiation field is along the axial direction of the machine frame of the radiotherapy system.

In some possible implementations, the short side of the pre-alignment hole is adjustable in size.

In another aspect, the embodiments of the present invention further provide a radiotherapy apparatus, which includes any one of the treatment heads described above.

The technical scheme provided by the embodiment of the utility model has the beneficial effects that at least:

according to the embodiment of the utility model, the first blade and the second blade move along the direction parallel to the axis of the frame of the radiotherapy system (the axial direction of the frame is defined as the Y direction), so that the opening and closing directions of the first blade and the second blade are always parallel to the axis direction of the frame no matter the treatment head rotates to any position along with the frame, the influence of gravity on the opening and closing of the blades is effectively avoided, and the accuracy of the multi-blade collimator in conforming to the ray bundle is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of an exemplary treatment head according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an exemplary multi-leaf collimator provided by the embodiment of the present invention, wherein fig. 2 is a top view of the multi-leaf collimator, and a leaf section in fig. 2 is a section in a leaf thickness T direction;

FIG. 3 is a schematic structural diagram of an exemplary leaf provided by an embodiment of the present invention, wherein FIG. 3 is a leaf structure obtained from a lateral direction of a multi-leaf collimator;

FIG. 4 is a schematic diagram of another exemplary multi-leaf collimator;

fig. 5 is a schematic structural diagram of a pre-collimator according to an embodiment of the present invention;

FIG. 6 is a top view of a pre-collimator according to an embodiment of the present invention;

FIG. 7 is a side view of a pre-collimator provided in accordance with an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of another pre-collimator according to an embodiment of the present invention;

FIG. 9 is a schematic structural diagram of another pre-collimator according to an embodiment of the present invention;

fig. 10 is a schematic view of a connection relationship between a fixed block and a slider according to an embodiment of the present invention.

The reference numerals denote:

100-treatment head, 200-frame, 300-treatment bed,

101-radiation source, 102-pre-collimator, 103-multileaf collimator,

11-the first blade or blades-are,

12-the second blade or blades, and,

21-the first drive mechanism,

22-a second drive mechanism-the second drive mechanism,

23-a third drive mechanism-the first drive mechanism,

201-a first transmission piece, which is,

202-a first driving member to be driven,

203-a second transmission member,

204-the second drive member,

3-position monitoring mechanism, 31-elastic piece, 32-force transducer,

41-a pre-collimator body, wherein,

411-the base body, and the base body,

412-a first fixed block, 413-a second fixed block,

414-a guide groove, which is provided with a guide groove,

415-first slider, 416-second slider,

42-pre-aligned holes, 421-first section, 422-second section,

5-fixing the part.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the following will describe embodiments of the present invention in further detail with reference to the accompanying drawings.

The radiotherapy system is a common tumor treatment device, and the radiotherapy system includes treatment couch, frame and treatment head, and the treatment couch can move along the axis direction of frame, and the treatment head bears in the frame, and the treatment head includes again: the collimator comprises a radiation source, a pre-collimator and a multi-leaf collimator, wherein the pre-collimator and the multi-leaf collimator are sequentially arranged on a path of a ray bundle emitted by the radiation source. The ray bundle emitted by the radiation source is firstly preliminarily conformed through the pre-collimating holes on the pre-collimator and then finally conformed through the final collimating holes on the multi-leaf collimator so as to limit the radiation range of the ray bundle, so that the final irradiation field is matched with the tumor shape of the patient.

In the related art, the treatment head is capable of rotating on its own axis, and the treatment head includes: the radiation field is matched with the tumor shape of a patient. The multi-blade collimator comprises a plurality of groups of blades which can be opened and closed along the radial direction of the frame. However, when the multi-leaf collimator is rotated to the side of the frame, the leaf opening and closing direction of the multi-leaf collimator is along the gravity direction thereof, and gravity may adversely affect the movement of the leaves.

The isocenter of the radiotherapy system refers to the intersection point of the rotation axis of the collimator body (which can be considered as the center of the irradiation field) and the rotation axis of the gantry. The collimator body refers to the whole body formed by the pre-collimator and the multi-leaf collimator.

The radiation field refers to the boundary of the radiation beam defined by the collimating body and the plane of the radiation beam perpendicular to the central axis of the radiation beam.

The axial direction of the stander refers to the axial direction of a central shaft of the stander, and the stander can rotate around the central shaft of the stander so as to drive the treatment head on the stander to synchronously rotate. The central axis of the stander is parallel to the central axis of the treatment couch.

An embodiment of the present invention provides a treatment head 100, which can be used in a radiation treatment system, as shown in fig. 1, the treatment head 100 includes: a radiation source 101, a pre-collimator 102 and a multi-leaf collimator 103; wherein, the pre-collimator 102 and the multi-leaf collimator 103 are sequentially arranged on the path of the radiation beam emitted by the radiation source 101, the pre-collimator 102 is configured to perform preliminary conformation on the radiation beam emitted by the radiation source 101, and the multi-leaf collimator 103 is configured to perform final conformation on the preliminary conformed radiation beam.

As shown in fig. 2, the multi-leaf collimator 103 includes: a plurality of blade sets arranged side by side; each blade group includes: a first blade 11 and a second blade 12 which are arranged oppositely;

the first blade 11 and the second blade 12 both move in a direction parallel to the axis of the gantry 200 of the radiation therapy system.

In the embodiment of the present invention, both the first leaf 11 and the second leaf 12 move along the direction parallel to the axis of the gantry 200 of the radiotherapy system (the axis of the gantry 200 is the direction of the straight line of the central axis, and the gantry 200 can rotate around the central axis, and the axis of the gantry 200 is defined as the Y direction in the embodiment of the present invention), so that the opening and closing directions of the first leaf 11 and the second leaf 12 are always parallel to the axis of the gantry 200 no matter the treatment head 100 rotates to any position along with the gantry 200, the influence of gravity on the leaves during opening and closing is effectively avoided, and the accuracy of the multi-leaf collimator 103 in conforming the radiation beam is improved.

In order to optimize this effect, the treatment head 100 is configured to be non-rotatable about its own axis, i.e., the treatment head 100 and the gantry 200 are always in a fixed relationship, and the treatment head 100 is not capable of rotational movement along the gantry 200, but only with the gantry 200.

In the treatment head 100, the radiation source 101, the pre-collimator 102, and the multi-leaf collimator 103 are all fixed so that the pre-collimator 102 and the multi-leaf collimator 103 are sequentially disposed on the path of the radiation beam emitted by the radiation source 101. Since the treatment head 100 cannot rotate, the corresponding pre-collimator 102 and multi-leaf collimator 103 cannot rotate correspondingly.

In some possible implementations, in the treatment head 100 provided in the embodiment of the present invention, as shown in fig. 1, the multi-leaf collimator 103 further includes:

a plurality of first drive mechanisms 21 corresponding one-to-one to the first blades 11, and a plurality of second drive mechanisms 22 corresponding one-to-one to the second blades 12;

the first driving mechanism 21 is connected to the first blade 11 and is used for driving the first blade 11 to move along the direction parallel to the axis of the frame 200;

the second drive mechanism 22 is connected to the second blade 12 for driving the second blade 12 to move in a direction parallel to the axis of the frame 200.

Through the arrangement, each blade in the multi-blade collimator 103 is driven independently by one corresponding driving mechanism, so that the specific first blade 11 and/or the specific second blade 12 are driven to conform, the conformity precision is improved, and the purpose of intensity modulated treatment is achieved.

When the field formed by the pre-collimator 102 becomes smaller, the moving distance of the multi-leaf collimator 103 when the leaves are opened and closed is also reduced accordingly, so that the maximum moving distance of the first leaf 11 and the second leaf 12 is also reduced compared with the prior art. In the embodiment of the present invention, the maximum movement distance of the first blade 11 and the second blade 12 is 5cm to 15cm, for example, 8cm or 10 cm.

For example, when the size of the radiation field in the axial direction of the gantry 200 of the radiotherapy system is 8cm, the maximum moving distance of the first blade 11 and the second blade 12 is 8 cm; when the size of the radiation field in the axial direction of the gantry 200 of the radiotherapy system is 10cm, the maximum moving distance of the first blade 11 and the second blade 12 is 10 cm. Compared with the prior art (the maximum distance of the blade movement is generally larger than 15cm, and the trolley movement can form a 40-40 cm field at the isocenter), in the embodiment of the utility model, the stroke of the blade is shortened, so that the length of the blade is shortened.

In the embodiment of the present invention, the first driving mechanism 21 is configured to be able to stop the first blade 11 at any position in the movement range; the second drive mechanism 22 is configured to enable the second blade 12 to dwell at any position within the range of motion.

So configured, each leaf can be moved to any point within the movable range of the leaf, which is beneficial to improve the conformal precision of the multi-leaf collimator 103.

In some possible implementations, as shown in fig. 2, the first drive mechanism 21 and the second drive mechanism 22 each include: a first transmission 201 and a first driver 202; the first transmission piece 201 is connected with the rear end of the first blade 11 or the second blade 12; the first driving member 202 is connected to the first transmission member 201.

That is, a first transmission member 201 is connected to the rear end of each first blade 11, and a first transmission member 201 is connected to the rear end of each second blade 12. Wherein, the rear end of the blade refers to the end opposite to the front end of the blade, and the front ends of the first blade 11 and the second blade 12 refer to the opposite ends, and the front end of the first blade 11 and the front end of the second blade 12 form a ray conformal area therebetween.

The first and second blades 11 and 12 are controlled by the first and second drive mechanisms 21 and 22, respectively, so that the first and second blades 11 and 12 can be automatically fixed at a set position after moving to the set position.

The transmission mode of the first transmission member 201 is exemplarily a screw transmission or a rack and pinion transmission, and the following description is respectively exemplary:

(1) when the transmission mode of the first transmission member 201 is a spiral transmission, as shown in fig. 2, the first transmission member 201 is a lead screw, the first driving member 202 is a linear motor (e.g., a micro linear motor), a first end of the lead screw is connected to the tail end of the first blade 11 (or the second blade 12), and a second end of the lead screw is connected to the linear motor.

The linear motor can drive the screw rod to do linear reciprocating motion, and further drive the first blade 11 (or the second blade 12) to do corresponding linear motion, so as to achieve the purpose of enabling the first blade 11 (or the second blade 12) to do linear reciprocating motion along the axial direction of the rack 200.

The second end of the screw rod can be connected with the linear motor through the rotor with the internal thread, and the first end of the screw rod is fixedly connected with the tail end of the first blade 11 (or the second blade 12), so that the rotary motion of the output shaft of the linear motor can be converted into the linear motion of the screw rod along the rotor, and the linear motion of the first blade 11 (or the second blade 12) is further driven.

Alternatively, the screw may be directly used as an output shaft of the linear motor while being threadedly coupled to the tail end of the first vane 11 (or the second vane 12), so that the rotation of the screw can be directly converted into the linear motion of the first vane 11 (or the second vane 12).

Based on the above, when the maximum moving distance of the first blade 11 and the second blade 12 is reduced compared to the maximum moving distance of the blades provided in the prior art, the length of the filament corresponding to each blade is also correspondingly shortened, which is not only beneficial to reducing the production difficulty of the multi-blade collimator 103, but also can increase the stability thereof and reduce the failure rate. In addition, the multi-leaf collimator 103 provided by the embodiment of the utility model does not need a trolley and other devices to increase the leaf stroke, thereby further reducing the complexity of the radiotherapy system.

(2) When the transmission mode of the first transmission member 201 is rack and pinion transmission, the first transmission member 201 includes: a gear and a rack engaged with each other, and the first driving member 202 is a micro motor. Wherein, the rack is fixedly connected with the first blade 11 (or the second blade 12), and the gear is coaxially connected with the micro motor.

When the micro motor is started, the gear can be driven to rotate, and then the rack meshed with the gear is driven to do linear motion, so that the moving rack drives the first blade 11 (or the second blade 12) to do linear motion.

Since the driving speed of the motor is variable, the moving speed and the moving position of the first blade 11 (or the second blade 12) can be accurately controlled, and thus, an accurate radiation intensity modulation effect can be obtained.

In the embodiment of the present disclosure, the first driving parts 202 of the first driving mechanism 21 and the second driving mechanism 22, for example, motors, are connected to a controller (for example, a PLC controller or a computer), and the controller may be connected to an upper computer at the same time.

In some possible implementations, the multi-leaf collimator 103 further includes: the first driving piece mounting plate is provided with a plurality of mounting positions for being respectively fixedly connected with the first driving pieces so as to fix the positions of the first driving pieces.

Further, the multi-leaf collimator 103 may further include: and the guide rail box is used for bearing all the blades so that the blades can stably move along the guide rail box when moving.

When the radiotherapy system comprising the multi-leaf collimator 103 provided by the embodiment of the utility model is used for tumor treatment, an operator can send an instruction for adjusting the moving distance of the leaves through the upper computer before treatment. Alternatively, the operator may send instructions to adjust the distance the blades are moved in real time during the treatment.

In the treatment process, the driving speed of the motor can be adjusted in real time to accurately control the movement speed and the movement position of the first blade 11 and the second blade 12, so as to realize dose intensity modulation in the treatment process.

In some possible implementations, the length directions of the first blade 11 and the second blade 12 are both parallel to the axial direction of the gantry 200 of the radiotherapy system;

as shown in fig. 3, the length L of each of the first blade 11 and the second blade 12 is 2.5cm to 7.5 cm;

the height H of the first blade 11 and the height H of the second blade 12 are both 6cm-8 cm.

The length directions of the first blade 11 and the second blade 12 are made parallel to the axial direction of the gantry 200 of the radiotherapy system (the axial direction of the gantry 200 is defined as the Y direction). In this way, when the first leaf 11 and the second leaf 12 are opened and closed, the leaf can always move along the axial direction of the gantry 200 of the radiotherapy system, thereby avoiding the influence of gravity on the multi-leaf collimator 103 when the leaf is opened and closed, and improving the accuracy of the multi-leaf collimator 103 in conforming the radiation beam.

In some possible implementations, the length L of the first blade 11 and the second blade 12 are both 2.5cm to 7.5cm, such as 3cm, 4cm, 5cm, 6cm, 7cm, and so forth. The length L of the leaf is the longest dimension in the longitudinal direction, and the leaf length enables the size of the leaf to be reduced, and the leaf of the multi-leaf collimator 103 is finally miniaturized.

In the embodiment of the utility model, the length of the blade is obviously reduced compared with the length (150mm) of the blade in the prior art, so that the size and the weight of the blade are reduced, and the processing difficulty and the manufacturing cost are reduced. The weight of the blades is reduced, friction and motion resistance are reduced, the motion is more convenient to control, the fault rate can be reduced, the blades can move faster under the same driving capability, and then the treatment quality is obviously improved.

Of course, the blade size is determined to some extent by the size of the field formed by the pre-collimator 102 at the isocenter, i.e. the reduction of the blade size depends on the reduction of the maximum size of the field formed by the pre-collimator 102. For example, when the field projected at the isocenter of the radiotherapy system by the pre-collimator hole 42 of the pre-collimator 102 is rectangular, it includes a long side and a short side, and when the length of the short side of the field is 8cm, the lengths of the first blade 11 and the second blade 12 may be set to 4 cm; when the length of the short side of the radiation field is 10cm, the lengths of the first blade 1111 and the second blade 1212 may be each set to 5 cm.

The height H of the first blade 11 and the second blade 12 is 6cm-8cm, for example, 6cm, 6.5cm, 7cm, 7.5cm, etc. Wherein, the direction of height of blade is along the transmission direction of bundle of rays, and in this height range, the blade not only can provide better ray conformal effect, still makes the blade miniaturization simultaneously.

In the plurality of blade groups according to the embodiment of the present invention, the thicknesses T of the first blade 11 and the second blade 12 are gradually reduced toward the middle from both sides. That is to say, in the blade group, the thickness of the blade is thinner the closer to the middle blade, and the thickness of the blade is thicker the closer to the two sides blades, so the arrangement is favorable for improving the accuracy of intensity modulation of the treatment area.

In some possible implementations, the opposite front ends of the first blade 11 and the second blade 12 are both provided in an arc-shaped structure, such as a circular arc shape, and further such as a semi-circular arc shape. The first blade 11 and the second blade 12 in the same blade group may have the same or different curvatures of their tips, and for example, the curvature of the tip of the first blade 11 may be made the same as the curvature of the tip of the second blade 12.

In the embodiment of the present invention, each of the first blade 11 and the second blade 12 includes: the rectangular body and be located the arc front end of rectangular body front end. The arc direction of the arc front ends of the first blade 11 and the second blade 12 is along the height direction of the blades, and the height direction of the blades refers to the direction along the emission direction of the ray bundle, that is, the direction perpendicularly passing through the screen shot shown in fig. 2.

According to the multi-leaf collimator 103 provided by the embodiment of the utility model, the opposite front ends of the first leaf 11 and the second leaf 12 are both provided with the arc-shaped structures, so that compared with the case that the front ends of the leaves are provided with straight lines, the arc-shaped front ends of the first leaf 11 and the second leaf 12 can reduce penumbra formed when a ray bundle passes through the multi-leaf collimator 103, and the treatment accuracy is favorably improved.

In order to further optimize the effect of reducing the penumbra, the radian of the front ends of the first blade 11 and the second blade 12 is inversely proportional to the thickness of the blades, i.e., the thicker the thickness T of the blades is, the smaller the radian of the front ends of the blades is; the thinner the thickness T of the blade, the greater the camber of the blade tip.

The radian of the front ends of the first blade 11 and the second blade 12 is in direct proportion to the distance between the blade and the isocenter of the radiotherapy system, namely, the larger the distance between the blade and the isocenter is, the larger the radian of the front ends of the blades is; the smaller the blade is spaced from the isocenter, the smaller the camber of the blade tip.

The radian of the front ends of the first blade 11 and the second blade 12 is proportional to the maximum movement distance of the blade, that is, the larger the maximum movement distance that the blade can move, the larger the radian of the front ends of the blades, the smaller the maximum movement distance that the blade can move, and the smaller the radian of the front ends of the blades.

In some possible implementations, as shown in fig. 4, the therapy head 100 provided in the embodiment of the present invention further includes: a position monitoring mechanism 3, the position monitoring mechanism 3 being configured to monitor the motion position of the first blade 11 and the second blade 12. The position monitoring mechanism 3 is used for accurately monitoring the motion displacement of the leaves, so that the conformal precision of the multi-leaf collimator 103 on the ray beam is further improved, and accurate radiotherapy is realized. For each blade, a position monitoring mechanism 3 is correspondingly provided.

As an example, as shown in fig. 4, the position monitoring mechanism 3 includes: the blade comprises a load cell 32 and an elastic member 31, wherein the load cell 32 is fixedly arranged, one end of the elastic member 31 is fixedly connected with the load cell 32, and the other end of the elastic member 31 is connected with the rear end of the first blade 11 (the second blade 12).

The load cell 32 can measure the magnitude of the force applied to the elastic member 31, and when the first blade 11 (the second blade 12) moves, the degree of tension of the elastic member 31 changes, and then the force detected by the load cell 32 changes, and the motion position of the first blade 11 (the second blade 12) is determined according to the detected force.

Further, the position monitoring mechanism 3 further includes a processor electrically connected to the load cell 32 for determining the movement position of the first blade 11 (the second blade 12) according to the force data measured by the load cell 32.

For example, the load cell 32 may be secured to a drive mounting plate or rail box of the multileaf collimator 103, or the like.

For the convenience of measurement, when the elastic member 31 is located between the rear end of the first blade 11 (the second blade 12) and the load cell 32, the elastic member 31 is just in a natural extension state when the blade is at the initial position, so that only the tensile force of the elastic member 31 needs to be measured when the blade moves, and when the blade returns to the initial position again, the theoretically applied tensile force is zero, and the measurement is more convenient.

For example, the elastic member 31 may be a spring, and the coefficient of the spring is fixed in a normal use range, so that the accuracy of the measurement data can be ensured. Of course, the elastic member 31 may further include: latex ribs, tubes, ropes, or rubber ribs, tubes, ropes, or other components with good elasticity and fixed picnic coefficient.

As another example, the position monitoring mechanism 3 is a laser rangefinder including: the device comprises a space wave transmitter, a space wave receiver and a processor, wherein the space wave transmitter can transmit a linearly propagated space wave, and the space wave transmitted by the space wave transmitter irradiates on the rear end surface of the first blade 11 (the second blade 12); the spatial wave receiver is disposed on the optical path of the reflected spatial wave reflected by the rear end surface of the first blade 11 (second blade 12), and receives the reflected spatial wave reflected by the rear end surface of the first blade 11 (second blade 12); the processor is connected with the space wave transmitter and the space wave receiver and determines the position of the corresponding blade according to the space wave transmitted by the space wave transmitter and the space wave received by the space wave receiver.

Illustratively, the spatial wave transmitters and/or spatial wave receivers are mounted on a drive mounting plate or a rail box of the multi-leaf collimator 103, or the like. Illustratively, the spatial wave is a laser, infrared, ultrashort wave, or ultrasonic wave, or the like.

In some possible implementations, as shown in fig. 5-7, the pre-collimator 102 includes: a pre-collimator body 41 and a pre-collimating hole 42 opened on the pre-collimator body 41;

the pre-collimation hole 42 is a quadrangular frustum pyramid-shaped through hole, and the pre-collimation hole 42 penetrates through the first surface and the second surface of the pre-collimator body 41 which are opposite to each other.

The shape of the pre-collimator body 41 includes, but is not limited to: a circular block, a rectangular block, a pentagonal block, or a block of other geometric shape, as long as it suffices to be properly installed in the treatment head of the radiation therapy system.

The structure of the quadrangular frustum shaped through hole is shown in fig. 5, which has two sets of inclined inner sides opposite to each other in pairs, so that the first section of the pre-collimating hole 42 on the first surface of the pre-collimator body 41 is different from the second section of the pre-collimating hole 42 on the second surface of the pre-collimator body 41 in size.

The inclined inner side surfaces of the pre-alignment holes 42 may have the same or different inclination angles, as long as the sizes of the first and second sections of the pre-alignment holes 42 are different, for example, the inclination angles of the four inner side surfaces of the pre-alignment holes 42 may be the same. The cross section of the pre-alignment hole 42 may be rectangular or square.

The first and second surfaces of the pre-collimator body 41, which are oriented according to the cross-sectional dimensions of the pre-collimator hole 42 at the first and second surfaces of the pre-collimator body 1, refer to the surfaces of the pre-collimator body 41 facing the radiation source and facing the multi-leaf collimator. The surface of the end of the pre-collimation aperture 42 with the smaller cross-sectional dimension is facing the radiation source and the surface of the end of the pre-collimation aperture 42 with the larger cross-sectional dimension is facing the multi-leaf collimator.

The bundle of rays that sends by radiation source 101 can disperse behind the pre-collimation hole 42 of quadrangular frustum of a prism form through-hole structure for the bundle of rays that sends out by pre-collimation hole 42 has great field area, ensures that bundle of rays can cover the final collimation hole completely, simultaneously, still does benefit to the volume that reduces pre-collimator 102.

In some possible implementations, the first section 421 of the pre-collimation hole 42 and the second section 422 of the pre-collimation hole 42 are both elongated holes;

the size of the first section 421 of the pre-collimation hole 42 is larger than the size of the second section 422 of the pre-collimation hole 42;

wherein the first section 421 of the pre-collimation hole 42 is a section of the pre-collimation hole 42 on the first surface of the pre-collimator body 41;

the second section 422 of the pre-collimation hole 42 is a section of the pre-collimation hole 42 on the second surface of the pre-collimator body 41.

In use, a first surface of the pre-collimator 102 is facing the multileaf collimator 103 and a second surface of the pre-collimator 102 is facing the radiation source 101.

Based on the above, as shown in fig. 6, the first cross section and the second cross section of the pre-alignment hole 42 are both elongated holes (i.e., rectangles), and the elongated holes have long sides and short sides with different lengths, i.e., the pre-alignment hole 42 has long sides and short sides. By the structure of the pre-collimation hole 42 arranged in the above manner, the radiation beam emitted by the radiation source 101 can form a rectangular radiation field at the isocenter position after passing through the pre-collimation hole 42.

When the pre-collimator 102 provided by the embodiment of the present invention is used in a radiation therapy system, the short side of the pre-collimator hole 42 is oriented along the axial direction of the gantry 200 of the radiation therapy system.

The shape of the radiation field projected by the pre-collimation hole 42 having a cross-sectional shape of a rectangular hole at the isocenter of the radiotherapy system is correspondingly rectangular, which includes a long side and a short side, and the direction of the short side of the radiation field is along the axial direction of the gantry 200 of the radiotherapy system.

In some possible implementations, the short side of the portal is made 5cm-15cm in length, e.g., 5cm, 6cm, 7cm, 8cm, 9cm, 10cm, 11cm, 12cm, 13cm, 14cm, 15cm, etc.; the length of the long side of the radiation field is 30cm-50cm, such as 30cm, 35cm, 40cm, 45cm, 50cm, etc.

For example, the dimensions of the field projected by the pre-collimation hole 42 at the isocenter of the radiation therapy system are as follows: the short side length of the portal is 8cm or 10cm, and the long side length of the portal is 40 cm.

According to the size of the radiation field, the size of the pre-collimation hole 42 at any distance from the isocenter can be obtained accordingly, and further, the size of the first section 421 of the pre-collimation hole 42 and the size of the second section 422 of the pre-collimation hole 42 can be obtained. The size of the radiation field provided by the embodiment of the utility model enables the size of the pre-collimation hole 42 to be correspondingly smaller, which is beneficial to reducing the size and volume of the pre-collimator 102, and further facilitates the simplification of the volume and structure of the treatment head 100.

In some possible implementations, the pre-collimation hole 42 of the pre-collimator 102 provided by the embodiment of the present invention is adjustable in size, which includes but is not limited to: the long side of the pre-alignment hole 422 may be adjustable, or the short side of the pre-alignment hole 42 may be adjustable, or both the long side and the short side of the pre-alignment hole 42 may be adjustable.

The size of the pre-collimation hole 42 is variable, so that different primary conformal effects of ray beams can be obtained, the pre-collimation hole is suitable for different sizes of lesion areas, and the adaptability of the pre-collimator 102 is improved. Further, when the size of the pre-alignment hole 42 is changed to 0, that is, when the pre-alignment hole 42 is closed, it is also possible to perform a source-off or an intensity-modulated treatment without irradiation.

In some possible implementations, the short side of the pre-collimation hole 42 is made adjustable in size, so that in the application state of the pre-collimator 102, the size of the pre-collimation hole 42 in the axial direction of the gantry 200 of the radiotherapy system is adjustable to fit different size of lesion fields.

It should be noted that the size of the short side of the pre-alignment hole 42 is adjustable, which means that the size of the short side of any cross section of the pre-alignment hole 42 is adjustable in the whole depth direction of the pre-alignment hole 42.

For how the adjustable short side size of the pre-alignment straight hole 42 is realized, the following exemplary description is given in the embodiment of the present invention:

in some possible implementations, as shown in fig. 8 or fig. 9, the pre-collimator body 41 includes: a base 411 having a through hole, a first fixing block 412, a second fixing block 413, a first slider 415, and a second slider 416;

the first fixing block 412 and the second fixing block 413 are fixed to opposite first side portions of the through hole to form two short sides of the pre-alignment straight hole 42 in a matching manner;

the first slider 415 and the second slider 416 are located at the opposite second side of the through hole to cooperate with the two long sides constituting the pre-alignment hole 42, and the distance between the first slider 415 and the second slider 416 is adjustable.

The base 411, the first fixed block 412, the second fixed block 413, the first slider 415, and the second slider 416 are made of a radiation shielding material, such as tungsten, lead, or a tungsten alloy. Also, the shape of the base 411 includes, but is not limited to: a circular block, a rectangular block, a pentagonal block, or a block of other geometric shape, as long as it is satisfactory to be properly installed in the treatment head 100 of the radiation therapy system.

By moving the first slider 415 and the second slider 416, the distance between the two sliders can be adjusted, so that the size of the short side of the pre-alignment hole 42 can be adjusted.

For example, the first slider 415 and the second slider 416 may be moved as follows, so as to adjust the distance between the two sliders: the first slider 415 and the second slider 416 move by a slide rail transmission, the first slider 415 and the second slider 416 move by a rack and pinion transmission, the first slider 415 and the second slider 416 move by a lead screw nut transmission, and the like. These are exemplified in the following, respectively:

as an example, the first and second fixing blocks 412 and 413, and the first and second sliders 415 and 416 may be respectively positioned at both sides of the top of the through-hole of the base 411, so that the pre-alignment hole 42 formed by each fixing block and each slider is actually positioned above the through-hole of the base 411. In this implementation, the size of the through-hole is made larger than the maximum size to which the pre-collimation hole 42 can be adjusted to ensure that the desired field is obtained.

As another example, the first and second fixing blocks 412 and 413, and the first and second sliders 415 and 416 may be respectively located at both inner sides of the through-hole of the base 411, so that the pre-alignment hole 42 formed by each fixing block and each slider is actually integrated with the through-hole of the base 411.

In this implementation, the size of the through hole may be adaptively determined according to the sizes of the fixed block and the slider, and the required field size.

Wherein, a sliding groove (the sliding groove is equivalent to a guide groove 414 described below) is provided on the opposite second side of the through hole of the base 411 for accommodating the tail portions of the first slider 415 and the second slider 416 respectively and enabling the tail portions of the first slider 415 and the second slider 416 to move along the sliding groove, and the front portions of the first slider 415 and the second slider 416 are opposite for constituting the beam conformal region. The structure of the opposite sides of the first and second fixed blocks 412 and 413 is adapted to the structure of the sides of the first and second sliders 415 and 416, for example, the opposite sides of the first and second fixed blocks 412 and 413 are in surface contact with the sides of the first slider 415 to move the first and second sliders 415 and 416 along the surfaces of the sides of the fixed blocks. Alternatively, as shown in fig. 6, guide grooves 1201 are formed on the opposite surfaces of the first fixed block 412 and the second fixed block 413, and the opposite sides of the first slider 415 and the opposite sides of the second slider 416 are respectively inserted into the corresponding guide grooves 1201, so that the first slider 415 and the second slider 416 both move along the guide grooves 1201.

For both examples, one of the first slider 415 and the second slider 416 may be fixed and the other may be moved, for example, the second slider 416 may be fixed and the first slider 415 may be moved in a direction away from or close to the second slider 416; alternatively, the first slider 415 and the second slider 416 may be movable, and may be moved toward each other or away from each other.

In order to make the movement of the first slider 415 and the second slider 416 more stable and smooth, in the embodiment of the present invention, as shown in fig. 10, guide grooves 414 are respectively disposed on the opposite surfaces of the first fixed block 412 and the second fixed block 413, and the opposite sides of the first slider 415 and the opposite sides of the second slider 416 are respectively inserted into the corresponding guide grooves 414, so that the first slider 415 and the second slider 416 both move along the guide grooves 414.

Illustratively, the cross-sectional shape of the guide groove 414 includes, but is not limited to: rectangular, trapezoidal, circular arc, etc., and accordingly, both sides of the first slider 415 and the second slider 416 facing each other are also rectangular, trapezoidal, circular arc, etc.

The guide groove 414 on the fixed block not only can provide a guide effect for the movement of the sliding block, but also can provide a certain limiting effect for the sliding block, and is favorable for improving the stability of the sliding block during movement.

After the first slider 415 and the second slider 416 move to the set position along the guide groove 414, the first slider 415 and the second slider 416 need to be fixed, and the fixing manner of the sliders includes, but is not limited to, the following:

in some possible implementations, the sliding block is manually fixed, and in this implementation, as shown in fig. 4, the pre-collimator 102 provided by the embodiment of the present invention further includes: and a fixing member 5, wherein the fixing member 5 is configured to fix the first slider 415 and the second slider 416 in a moving state.

When the first slider 415 and the second slider 416 move to the set position, the first slider 415 and the second slider 416 are fixed by the fixing member 5, so that the first slider 415 and the second slider 416 are fixed at the set position. The fixing of the fixing member 5 to the first slider 415 will be described below as an example to illustrate the structure of the fixing member 5 (the fixing principle of the fixing member 5 to the second slider 416 is the same as that of the fixing member to the first slider 415, and is not described in detail here):

as an example, the fixing member 5 includes: the first fixing bolt is arranged on the top wall of the first sliding block 415, one end of the pressing plate is rotatably connected with the top of the first fixing block 412 and/or the top of the second fixing block 413, a first bolt hole is formed in the other end of the pressing plate, a first bolt groove is formed in the top wall of the first sliding block 415, the first bolt groove is long in strip shape, and the length of the first bolt groove extends along the movement direction of the first sliding block 415. The first bolt slot is in communication with the first bolt hole.

After the first sliding block 415 moves to the set position, the first fixing bolt can pass through the first bolt hole to enter the first position of the first bolt groove and is simultaneously in threaded connection with the first bolt hole, so that the pressing plate presses the first sliding block 415, the first sliding block 415 is pressed on the top of the base 411, and the purpose of fixing the first sliding block 415 is achieved. When the position of the first sliding block 415 needs to be adjusted, the first fixing bolt is detached, the pressing plate is rotated to enable the pressing plate not to press the first sliding block 415 any more, after the first sliding block 415 is moved to a desired position, the pressing plate is rotated reversely to enable the first bolt hole on the pressing plate to be communicated with the second position of the first bolt groove on the first sliding block 415, so that the first fixing bolt can penetrate through the first bolt hole to enter the second position of the first bolt groove and is in threaded connection with the first bolt hole at the same time, and the purpose of pressing the first sliding block 415 is achieved.

And simultaneously with first bolt hole threaded connection to make the clamp plate compress tightly first slider 415, reach the purpose of fixing first slider 415.

As another example, the fixing member 5 includes: a plurality of second bolt grooves arranged side by side are formed in the side wall of the first slider 415 of the second fixing bolt, the second bolt grooves are sequentially arranged along the moving direction of the first slider 415, a second bolt hole is formed in the side wall of the first fixing block 412 or the second fixing block 413, the second bolt hole is long in strip shape, and the length of the second bolt hole extends along the moving direction of the first slider 415. The second bolt hole communicates with the second bolt groove, and both can be screwed with the second fixing bolt at the same time.

After the first sliding block 415 moves to the set position, the second fixing bolt can pass through the second bolt hole to enter the second bolt groove, and meanwhile, the second fixing bolt and the second bolt groove are in threaded connection, so that the purpose of fixing the first sliding block 415 is achieved.

In some possible implementations, as shown in fig. 9, the first slider 415 and the second slider 416 are both moved by the driving of the third driving mechanism 23; wherein the third drive mechanism 23 includes: a second transmission member 203 connected to the first slider 415 and the second slider 416, respectively; a second driving member 204 connected to the second transmission member 203.

The first slider 415 and the second slider 416 are respectively provided with one third driving mechanism 23, and the first slider 415 and the second slider 416 are respectively controlled individually by the two third driving mechanisms 23. In the embodiment of the present invention, the third driving mechanism 23 is used to automatically control the movement process of the first slider 415 and the second slider 416, so that the first slider 415 and the second slider 416 can be automatically fixed at the set position after moving to the set position.

The transmission mode of the second transmission member 203 is exemplarily a screw transmission or a rack and pinion transmission, and the following are respectively exemplified:

(1) as shown in fig. 9, when the transmission mode of the second transmission member 203 is a spiral transmission, the second transmission member 203 is a screw rod, the second driving member 204 is a linear motor (micro linear motor), a first end of the screw rod is connected to the tail end of the first slider 415 (the tail end of the first slider 415 is an end of the first slider 415 far away from the second slider 416), and a second end of the screw rod is connected to the linear motor.

The linear motor can drive the screw rod to do linear reciprocating motion, so as to drive the first sliding block 415 to do corresponding linear motion, and the purpose of enabling the first sliding block 415 to do linear reciprocating motion along the central axis direction of the rack 200 is achieved.

The second end of the screw rod can be connected with the linear motor through the rotor with the internal thread, and the first end of the screw rod is fixedly connected with the tail end of the first sliding block 415, so that the rotary motion of the output shaft of the linear motor can be converted into the linear motion of the screw rod along the rotor, and the first sliding block 415 is driven to move linearly.

Or, the screw rod may be directly used as an output shaft of the linear motor, and the screw rod is connected to the tail end of the first slider 415 by a thread, so that the rotation of the screw rod can be directly converted into the linear motion of the first slider 415.

(2) When the transmission mode of the second transmission member 203 is rack and pinion transmission, the second transmission member 203 includes: a gear and a rack which are meshed with each other, and the second driving member 204 is a micro motor. Wherein, the rack is fixedly connected with the first slide block 415, and the gear is coaxially connected with the micro motor.

When the micro motor is started, the gear can be driven to rotate, and then the rack meshed with the gear is driven to do linear motion, so that the moving rack drives the first sliding block 415 to do linear motion.

Since the driving speed of the motor is variable, the moving speed and the moving position of the first slider 415 and the second slider 416 can be accurately controlled, and thus, an accurate radiation intensity modulation effect can be obtained.

In the embodiment of the present disclosure, the motor of the third driving mechanism 23 is connected to a controller (for example, a PLC controller), the controller may be connected to an upper computer, an operator may send a command for adjusting the length of the short side of the pre-alignment hole 42 to the controller by operating the upper computer, and the controller drives the motor to control the movement of the slider after receiving the command, thereby achieving the purpose of obtaining the pre-alignment hole 42 with a specific size.

When the radiation therapy system including the pre-collimator 102 provided in the embodiment of the present invention is used to perform tumor therapy, the operator may send a command for adjusting the size of the pre-collimating hole 42 through the upper computer before therapy, so as to adjust the width of the pre-collimating hole 42 to a set width value. Alternatively, the operator may also send instructions to adjust the size of the pre-alignment holes 42 in real time during the treatment.

During the treatment, the driving speed of the motor can be adjusted in real time to accurately control the moving speed and the moving position of the first slider 415 and the second slider 416.

The following is a brief description of the other components included in the radiation therapy system, respectively: for a couch 300, which may be disposed on a floor for supporting a patient, the couch 300 is configured to be movable to change the position of the patient.

For the rack 200, it may include: fixed frame and rotating frame, wherein, fixed frame is fixed to be set up subaerial, rotating frame and fixed frame rotatable coupling, simultaneously, rotating frame still with treatment head 100 fixed connection, rotating frame can drive treatment head 100 rotatory around the center pin of rotating frame, treatment head 100 can rotate along with rotating frame like this, and treatment head 100 still can not take place the rotation simultaneously.

In the embodiment of the present invention, the structure of the rotating frame includes but is not limited to: a ring-shaped structure, a C-shaped structure, a helmet-shaped structure, etc.

In embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The term "plurality" means two or more unless expressly limited otherwise.

The above description is only for facilitating the understanding of the technical solutions of the present invention by those skilled in the art, and is not intended to limit the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A therapy head, characterized in that it comprises: a radiation source, a pre-collimator and a multi-leaf collimator;

the pre-collimator and the multi-leaf collimator are sequentially arranged on the path of the radiation beam emitted by the radiation source, the pre-collimator is configured to perform primary conformity on the radiation beam emitted by the radiation source, and the multi-leaf collimator is configured to perform final conformity on the primarily conformed radiation beam;

the multileaf collimator includes: a plurality of blade sets arranged side by side; each blade group includes: the first blade and the second blade are oppositely arranged;

the first vane and the second vane each move in a direction parallel to an axis of a gantry of a radiation therapy system.

2. The applicator according to claim 1, wherein the applicator is configured to be non-rotatable about its axis.

3. The therapy head of claim 1, wherein the multi-leaf collimator further comprises:

a plurality of first drive mechanisms corresponding to the first blades one to one, and a plurality of second drive mechanisms corresponding to the second blades one to one;

the first driving mechanism is connected with the first blade and used for driving the first blade to move along the direction parallel to the axis of the rack;

the second driving mechanism is connected with the second blade and used for driving the second blade to move along the direction parallel to the axis of the rack.

4. The therapy head according to claim 3, wherein the maximum movement distance of the first blade and the second blade is 5cm-15 cm;

and the first drive mechanism is configured to be able to stop the first blade at any position within a range of motion;

the second drive mechanism is configured to enable the second blade to stop at any position within a range of motion.

5. The treatment head of claim 1, wherein the length directions of the first and second leaves are both parallel to an axial direction of a gantry of the radiation therapy system;

the lengths of the first blade and the second blade are both 2.5cm-7.5 cm;

the heights of the first blade and the second blade are both 6cm-8 cm.

6. The therapy head according to claim 1, wherein opposing leading ends of the first and second blades are each provided in an arcuate configuration.

7. The treatment head according to any of claims 1-6, wherein the pre-collimator comprises: the pre-collimator comprises a pre-collimator body and a pre-collimating hole formed in the pre-collimator body;

the pre-collimation hole is a quadrangular frustum pyramid-shaped through hole, and penetrates through the first surface and the second surface of the pre-collimator body, wherein the first surface and the second surface are opposite.

8. The treatment head according to claim 7, wherein the pre-collimation aperture projects a field at the isocenter of the radiotherapy system in the shape of a long bar;

the length of the short side of the radiation field is 5-15 cm;

the length of the long edge of the radiation field is 30-50 cm;

wherein the short side direction of the radiation field is along the axial direction of the machine frame of the radiotherapy system.

9. The treatment head according to claim 8, wherein the short side of the pre-alignment hole is adjustable in size.

10. A radiotherapy apparatus, characterized in that it comprises: a treatment head as claimed in any one of claims 1 to 9.

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