JP2001340474A - Radiation treatment planning method and medical device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To quickly and easily confirm a set position when positioning a patient at the time of treatment, and to irradiate the set position with deviation due to position setting or respiration. In this case, a radiation treatment planning method and a medical apparatus capable of calculating a dose reflecting the deviation or performing a plan for correcting the deviation are obtained. SOLUTION: A radiation treatment planning apparatus 1 forms an irradiation field shape of a multi-leaf collimator reflecting the position of a patient 8, adds this irradiation field shape to normal treatment plan data, and sends it through a linac operation device 14. Then, the irradiation field shape is projected onto the patient 8 by the treatment device 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation treatment planning method for radiation treatment using a medical linac and a medical device used for implementing the method.

[0002]

2. Description of the Related Art A conventional radiation treatment planning apparatus sets an irradiation condition based on a CT image, calculates a dose, and transfers the irradiation condition to the treatment apparatus. Generally, there is no special function for confirming the set position deviation.

[0003]

Since the conventional radiation treatment planning apparatus is configured as described above, only the linac graph is taken or the irradiation field is manually positioned in order to confirm the position of the patient. There was a problem that the data had to be set and transferred so that they could be matched.

In addition, when an image is taken with a linac graph, printing cannot be performed such that the positions are superimposed to easily determine a shift, and the shift cannot be corrected. There is a problem in that it is not possible to set the enlargement ratio and print the contour which is displayed in the BEV mode.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to quickly and easily confirm a set position when positioning a patient during treatment. A radiation treatment planning method and a medical device that can perform dose calculation that reflects this deviation when irradiation occurs due to a deviation in the position due to position setting or respiration, and can perform a plan to correct this deviation. The purpose is to provide.

[0006]

According to a first aspect of the present invention, there is provided a radiation treatment planning method, comprising: a step of forming an irradiation field shape of a multi-leaf collimator reflecting a position of a subject; Is added to the normal treatment plan data and transferred to the treatment device.

According to a second aspect of the present invention, there is provided a radiation treatment planning method according to the first aspect, wherein the step of displaying the contour suitable for the positioning of the subject by BEV and the enlargement ratio of the BEV display are set. The method includes a step of printing and a step of superimposing the printed outline and an image captured by Linac Graph to check whether the positions are aligned.

In a third aspect of the present invention, there is provided a radiation treatment planning method according to the second aspect of the present invention, wherein the position of the printed contour and the image taken by the linac graph are shifted from each other. The value of the shift is taken in, and a calculation reflecting the influence of the shift is performed.

According to a fourth aspect of the present invention, there is provided a radiation treatment planning method according to the third aspect, wherein the deviation value is corrected.

According to a fifth aspect of the present invention, there is provided a radiation treatment planning method according to the first aspect of the present invention, wherein a fixture is used in a treatment plan of a surgery and an SRS localizer for position confirmation is used. A step of BEV displaying a contour suitable for the position of the subject and the position of the subject; a step of setting and printing an enlargement ratio of the BEV display;
Superimposing the printed outline and the image captured by the linac graph to check whether the positions are aligned.

A medical device according to the invention, an irradiation field shape forming means for forming an irradiation field shape of a multi-leaf collimator reflecting a position of a subject, and an irradiation field formed by the irradiation field shape forming means. Transfer means for adding a shape to normal treatment plan data and transferring the data to a treatment device, wherein the treatment device projects the irradiation field shape onto the subject.

A medical device according to the invention of claim 7, and a medical device according to claim 6.
The invention according to claim 1, further comprising a printing means for displaying the outline suitable for the positioning of the subject on a BEV display, setting an enlargement factor, and printing the image, and superimposing the printed outline on the image taken by the linac graph. This is to confirm that the values match.

The medical device according to the invention of claim 8 and the medical device according to claim 7.
In the invention according to the invention, when there is a shift in the position where the printed outline and the image captured by the linac graph are overlapped, the value of the shift is taken in, and the calculation reflecting the influence of the shift is performed. Means.

A medical device according to the ninth aspect of the present invention,
The invention according to the fifth aspect, further comprises an irradiation plan correcting means for correcting the deviation value.

According to a tenth aspect of the present invention, in the medical device of the sixth aspect, when using an SRS localizer for position confirmation using a fixing tool in a treatment plan of a surgery, the position of the point of the SRS localizer is determined. A printing means for displaying a contour suitable for the positioning of the subject on the BEV display, setting an enlargement ratio, and printing, and superimposing the contour printed by the printing means on the image taken by the linac graph is used. This is to confirm that they match.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. Embodiment 1 FIG. 1 to 4 show a first embodiment of the present invention.
FIG. 1A is a schematic configuration diagram of a radiation treatment planning apparatus, and FIG. 1B is a diagram illustrating setting of a target and an irradiation field on a CT image displayed on the image display display. . FIG. 2 is a configuration diagram of a linac (radiation therapy apparatus that performs treatment by irradiating radiation based on treatment plan data), FIG. 3 is a diagram illustrating a flow of treatment plan data,
FIG. 4 is a diagram showing the shape of a BEV irradiation field.

In each of the figures, 1 is a radiation treatment planning apparatus (RTP), 2 is a computer (EWS) main body, 3 is an image display, 4 is a CT image, 5 is a target as a treatment target site, 6 is an irradiation range, 7 is a body contour, 8 is a patient as a subject, 9 is a treatment table, 10 is a linac gantry, 11 is an X-ray source, 12 is an X-ray film, 13 is a linac body, 14 is a linac operating device, and 15 is a linac operating device. Linac, 16 is a BEV display, and 17 is an irradiation field (where X-rays hit) by a multi-leaf collimator.

Next, the operation will be described. First, RT
In the computer main body 2 of P1, an irradiation field shape is created by using an irradiation field shape creating means (not shown) for reflecting the position of the patient 8 on the shape of the irradiation field 15 of the multi-leaf collimator, and this is used for normal treatment. The data is supplied to the linac operating device 14 as transfer means in addition to the plan data. The linac operating device 14 transfers the treatment plan data to which the irradiation field shape is added to the linac 15. The linac 15 sets the treatment plan data in the linac body 13 and places the patient 8 on the treatment table 9. Then, the irradiation field shape set by the operation of the linac main body 13 is projected onto the body surface of the patient 8, and the position of the patient 8 is confirmed at this time, for example, in the light irradiation field as shown in FIG. .

FIG. 4A shows a treatment irradiation field in a BEV irradiation field shape, and FIG. 4B shows a positioning irradiation field in the same BEV irradiation field shape. In FIG. XY looking at the patient 8 at a distance of, for example, 1 m
FIG. 3 shows a plan view of an axis.

As described above, in this embodiment, the irradiation field shape reflecting the position of the patient is created, added to the normal treatment plan data, transferred to the linac via the linac operating device, and Then, since the treatment plan data is set and the set irradiation field shape is projected on the body surface of the patient on the treatment table, the position of the patient can be easily confirmed in the light irradiation field.

Embodiment 2 FIG. FIG. 5 is a block diagram showing Embodiment 2 of the present invention. In the figure, 18 is a scanner, 19 is a graphic input device (digitizer),
Both are connected to the computer main body 2 of RTP1. Other configurations are the same as those in the first embodiment.

Next, the operation will be described. First, after setting the position of the patient 8 as described above, a linac graph (taking out a weak X-ray from the X-ray source 11 of the linac 13 and taking an X-ray photograph for position confirmation) is taken. Further, a printing unit (not shown) prints an outline of positioning equivalent to the X-ray photograph in the RTP1 by using a printing unit (not shown), and a position shift is confirmed by superimposing this on a linac graph.

When the patient 8 is set up on the couch 9, it is inevitable that the patient 8 moves with pain or moves with breathing. These movements are captured by the X-ray film 12 and are read by the scanner 18 and the digitizer 1.
9 to the RTP1 to enable the BEV to superimpose and display the previous irradiation field.

As described above, in the present embodiment, the positional deviation can be easily confirmed by overlaying the linac graph on the positioning contour equivalent to the positional relationship with the X-ray photograph, and the patient set up on the treatment table can be used. Even if you move due to pain or breathing, this movement is captured in RTP with X-ray film, and BE
With V, it becomes possible to superimpose and display the previous irradiation field.

Embodiment 3 FIG. 6 is a BEV display diagram showing Embodiment 3 of the present invention. Note that the configuration of the present embodiment may use the same device as in the first embodiment. In the present embodiment, when there is a positional deviation by overlapping the linac graph with the positioning contour having the same positional relationship as the X-ray photograph as described above, the value of the deviation is used as in the second embodiment. Is taken into the RTP1, the displacement amount is calculated by the body contour 7 as shown in FIG. 6, and the dose calculation at the shifted position is performed by the calculation means (not shown) to obtain the dose distribution.

As described above, in the present embodiment, when there is a shift, the shift amount is calculated based on the body contour, the dose is calculated at the shifted position, and the dose distribution is obtained. The irradiation dose distribution can be determined.

Embodiment 4 7A and 7B show a fourth embodiment of the present invention. FIG. 7A is a diagram showing a deviation of a dose distribution, and FIG. 7B is a diagram showing irradiation corrected for the deviation. Note that the configuration of the present embodiment may use the same device as in the first embodiment. In the present embodiment, a correction means (not shown) of an irradiation plan for correcting the value of the deviation in RTP1 in the third embodiment as shown in FIG. 7B is provided, and the deviation corrected by this correction means is provided. Is transferred to the linac 15 via the linac operating device 14 to perform the treatment.

This is to additionally irradiate the area where the radiation did not hit the target 5. Although it is not possible to erase what has hit an unnecessary portion, unnecessary irradiation can be minimized.

As described above, in the present embodiment, the target dose distribution can be brought closer to the target dose distribution by correcting the deviation value using the RTP and transferring the deviation value to the linac via the linac operating device for treatment.

Embodiment 5 8 and 9 show Embodiment 5 of the present invention. FIG. 8 is a block diagram of the fifth embodiment, and FIG. 9 is a diagram showing confirmation by an SRS localizer. The confirmation is performed by calculating a body contour. In FIG. 8,
Parts corresponding to those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted. Other configurations are the same as those in the first embodiment. In the figure, reference numeral 20 denotes an SRS provided above and below the head of the patient 8 between the gantry 10 and the X-ray film 2.
A localizer 21 is a localizer marker (four points).

Next, the operation will be described. Surgery, the same isocenter (the center of rotation of the linac and Z
By rotating the gantry 10 (Y axis) or rotating the treatment table 9 (Z axis) with respect to the intersection of the axes) and irradiating the same part from various directions and performing condensing irradiation, only the affected part is operated like surgery. When a fixture is used in a treatment plan for treatment in which the dose is concentrated and the dose to other parts is reduced, the irradiation field for position confirmation is transferred as shown in FIG. When the localizer 20 is used, a contour suitable for positioning the position of the point of the SRS localizer 20 and the position of the patient 8 is defined as:
As shown in FIG. 9, a BEV display 16 is set, an enlargement ratio is set, and printing is performed by a printing unit (not shown).

Then, the printed outline is superimposed on the X-ray film 12 or displayed.
The image 2 is captured by the scanner 18 or the digitizer 19 (both shown in FIG. 5) and displayed on the BEV, and it is confirmed whether or not the image is superimposed on the image captured by the LINAC graph at the time of transfer.

As described above, according to the present embodiment, the position of the irradiation field of the position confirmation for performing the surgery treatment and the focused irradiation is transferred to confirm the position, and when the SRS localizer is used, the point of this localizer is used. The position suitable for the position of the patient and the contour suitable for the positioning of the patient are displayed in BEV, and the magnification is set and printed. Thus, it is possible to accurately and easily confirm whether the displayed image is displayed on the BEV and the position is superimposed on the image captured by the linac graph.

[0034]

As described above, according to the first aspect of the present invention, the step of forming the irradiation field shape of the multi-leaf collimator reflecting the position of the subject, and the step of forming the formed irradiation field shape to the ordinary Since the method includes the step of adding to the treatment plan data and transferring the data to the treatment apparatus, the position of the subject can be easily and quickly confirmed, which contributes to shortening the treatment time.

According to the second aspect of the present invention, a step of displaying a contour suitable for the positioning of the subject in a BEV mode;
The method includes a step of setting and printing the enlargement ratio of the BEV display, and a step of superimposing the printed outline and an image captured by LINAC graph to check whether the positions are aligned. Even if it moves, the displacement can be easily confirmed, and the subject can be positioned efficiently in a short time.

According to the third aspect of the present invention, when there is a shift in the position where the printed outline and the image taken by the linac graph are overlapped, the value of the shift is taken in. Since the calculation reflects the effect of the shift,
The distribution of the dose actually irradiated can be obtained, and there is an effect that accurate treatment can be performed.

Further, according to the invention of claim 4, since the value of the deviation is corrected, it is possible to bring the target dose distribution closer to the target, thereby contributing to an improvement in treatment accuracy.

According to the fifth aspect of the present invention, when an SRS localizer for position confirmation is used in a treatment plan of a surgery by using a fixture, the position of a point of the SRS localizer and the position of the subject are aligned. Contour suitable for BEV
Displaying, setting the enlargement ratio of the BEV display, and printing, and superposing the printed outline and an image captured by LINAC graph to check whether the positions are aligned. Therefore, it is possible to accurately and easily confirm the positioning of the subject, which has the effect of improving the treatment accuracy and shortening the treatment time.

Further, according to the invention of claim 6, an irradiation field shape forming means for forming an irradiation field shape of the multi-leaf collimator reflecting the position of the subject, and an irradiation field formed by the irradiation field shape forming means Transfer means for adding the field shape to the normal treatment plan data and transferring it to the treatment apparatus, and the treatment apparatus projects the irradiation field shape onto the subject, so that the position of the subject can be easily and quickly determined. This has the effect of being able to confirm and contribute to shortening of the treatment time and the like.

According to the seventh aspect of the present invention, there is provided a printing means for displaying a contour suitable for the positioning of the subject in a BEV display, setting an enlargement factor, and printing, and printing the contour and the linac graph. It is possible to confirm whether the position is correct by superimposing the image captured in step (e), so that even if the subject moves, the displacement of the position can be easily confirmed, and the subject can be positioned efficiently in a short time. This has the effect.

According to the eighth aspect of the present invention, when there is a shift in the position where the printed outline and the image captured by the linac graph are overlapped, the value of the shift is taken in. Since the calculation means for performing the calculation reflecting the influence of the shift is provided, it is possible to obtain the dose distribution of the actually irradiated dose, which has an effect that the treatment can be performed with high accuracy.

According to the ninth aspect of the present invention, since the irradiation plan correcting means for correcting the deviation value is provided, the target dose distribution can be brought close to the target, thereby contributing to the improvement of treatment accuracy. There is.

Further, according to the tenth aspect of the present invention, the SRS for position confirmation using the fixing tool in the treatment plan of the surgery is provided.
When a localizer is used, a contour suitable for the position of the point of the SRS localizer and the position of the subject is set to B.
A printing unit for displaying an EV display and setting an enlargement ratio for printing is provided, and it is checked whether or not the outline printed by the printing unit and the image captured by the linac graph are superimposed on each other so that the position of the subject is checked. It is possible to accurately and easily confirm the positioning of the patient, which has the effect of improving the treatment accuracy and shortening the treatment time.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a main part of a first embodiment of the present invention and a CT image display diagram thereof.

FIG. 2 is a configuration diagram showing a main part of the first embodiment of the present invention.

FIG. 3 is a diagram showing a flow of treatment plan data according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a BEV irradiation field shape according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining how to capture a displacement according to the second embodiment of the present invention;

FIG. 6 is a diagram for explaining correction of a position shift according to the third embodiment of the present invention.

FIG. 7 is a diagram for explaining a deviation of a dose distribution and a correction thereof according to a fourth embodiment of the present invention.

FIG. 8 is a configuration diagram showing a main part of a fifth embodiment of the present invention.

FIG. 9 is a diagram for describing confirmation by an SRS localizer according to Embodiment 5 of the present invention.

[Explanation of symbols]

1 Radiation treatment planning device (RTP), 2 Computer (E
WS) body, 3 image display, 4 CT
Image, 5 Target to be treated, 6 Irradiation area, 7 Body contour, 8 Patient, 9 Treatment table, 1
0 Gantry of linac, 11 X-ray source, 1
2X film, 13 linac body, 14
Linac operation machine, 15 Linac, 16 BE
V display, 17 irradiation field by multi-leaf collimator, 18 scanner, 19 digitizer, 20 S
RS localizer.

Claims (10)

[Claims] 1. A step of forming an irradiation field shape of a multi-leaf collimator reflecting the position of a subject, and a step of adding the formed irradiation field shape to normal treatment plan data and transferring it to a treatment apparatus. A radiation treatment planning method, comprising: 2. A step of displaying an outline suitable for the positioning of the subject by BEV, a step of setting and enlarging the magnification of the BEV display, and an image captured by the linac graph with the printed outline. 2. A method of planning a radiation treatment according to claim 1, further comprising the step of: confirming the position by superimposing the positions. 3. When there is a shift in the position where the printed outline and the image taken by the linac graph are overlapped, a value of the shift is taken in and a calculation reflecting the influence of the shift is performed. 3. The method according to claim 2, wherein
The described radiation treatment planning method. 4. The radiation treatment planning method according to claim 3, wherein the deviation value is corrected. 5. When using a fixture in a treatment plan of a surgery and using an SRS localizer for position confirmation,
A step of displaying, by BEV, a contour suitable for the position of the point of the SRS localizer and the position of the subject; a step of setting and enlarging the BEV display; and a step of printing the contour and the linac graph. 2. The method according to claim 1, further comprising the step of superimposing the captured image to confirm whether the position is correct. 6. An irradiation field shape forming means for forming an irradiation field shape of a multi-leaf collimator reflecting a position of a subject, and the irradiation field shape formed by the irradiation field shape forming means is converted into normal treatment plan data. A medical device, further comprising: transfer means for transferring the irradiation field shape to the subject with the treatment device. 7. A printing means for displaying an outline suitable for the positioning of the subject on a BEV display, setting an enlargement ratio, and printing, and superimposing the printed outline on an image captured by a linac graph. 7. The medical device according to claim 6, wherein it is determined whether the position is correct. 8. When there is a shift in a position where the printed outline and an image captured by the linac graph are overlapped, a value of the shift is taken in, and a calculation reflecting the influence of the shift is performed. The medical device according to claim 7, further comprising a calculating unit. 9. The medical apparatus according to claim 8, further comprising an irradiation plan correction unit that corrects the deviation value. 10. When using a fixture in a treatment plan of a surgery and using an SRS localizer for position confirmation,
A printing means for displaying a contour suitable for the position of the point of the SRS localizer and the position of the subject on a BEV display, setting an enlargement ratio and printing, and imaging the contour printed by the printing means and a linac graph. 7. The method according to claim 6, further comprising: checking whether the position is correct by superimposing the selected image.
The medical device as described.