JPS5975A - Apparatus for automatically referring dose distribution in radiation treatment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention uses a radiation therapy machine such as a medical linear
A device for treating cancer by irradiating a patient with a lesion in the body, especially a radiation therapy machine, makes it easy for a radiologist to carry out the entire treatment according to a treatment plan made specifically for the patient. The present invention relates to an automatic dose distribution verification device for radiation therapy configured to automatically verify plans and implementation using a high-speed calculator.

Conventional automatic verification devices verify planned values and actual values only for parameters that have been set up for a certain patient for treatment. Therefore, it was impossible to verify the dose distribution itself, which is the most important thing for patients. Although dose distribution calculations have been performed in conventional treatment plans, there is no method that uses the resulting dose distribution as a subject for verification. Parameters such as the height, lateral position, and vertical position of the treatment bed on which the IIi patient is placed using the conventional automatic verification device, as well as the irradiation angle and irradiation aperture that aim at the patient's lesion center from the radiation source. size.

Based on parameters such as preset values representing the rotation angle of the X-ray head and the irradiation dose, a comparison is made between planned values and actual values in each numerical data. In other words, it is effective only for verification by conventional equipment and therapeutic inspection, and verification is possible when the planned dose distribution is obtained based on the assumption that the prescribed dose is irradiated from 6 gates. I took it seriously. There was no essential verification of changes in the distribution of absorbed radiation within the patient's body as treatment progressed, that is, as irradiation progressed.

The purpose of the present invention is to calculate and display the dose distribution according to changes in treatment parameters during the progress of radiotherapy, that is, while the radiotherapy machine is operating, and to display the distribution of radiation absorbed in the patient's body as the treatment progresses. By monitoring changes in the dose distribution and allowing the treating physician to monitor and verify how the dose distribution approaches the treatment plan, the above drawbacks can be overcome and the treatment effect maximized for the patient. An object of the present invention is to provide an automatic dose distribution verification device in radiation therapy that provides excellent clinical results.

In order to achieve the above object, the automatic dose distribution verification device for radiation therapy according to the present invention includes an input device for inputting treatment conditions or treatment parameters as data or numerical values while a patient is being treated by a radiation therapy machine; a high-speed calculation device that repeatedly calculates data or numerical values from the device nine times at high speed to calculate the absorbed dose distribution in the patient's body space that changes over time;
It includes an output device that displays a video superimposed on a T-image or an internal anatomy diagram, and quantitatively displays the progress of treatment as a temporal change in the absorbed dose distribution within the body. It is configured to allow doctors to check the treatment plan and treatment progress.

That is, in the present invention, numerical data of treatment parameters during treatment are continuously input by connecting the radiation therapy machine to the processor online, and the absorbed dose distribution in the patient's body is connected to the processor based on the data. Repeated calculations are performed in extremely short periods using high-speed arithmetic units,
The calculation result is displayed as a video image superimposed on both CT images representing the internal structure of the patient's body.

Furthermore, it is possible to draw and record the dose distribution as a treatment result, and also to record and save numerical data of treatment parameters as a treatment record.

Next, the present invention will be described in detail with reference to the drawings of an embodiment of the present invention.

FIG. 1 is a block diagram showing an embodiment of an automatic verification device according to the present invention. The device is controlled by a microprocessor 1 forming a central processing unit. Radiation therapy machine 2
A linear search is used. Data regarding the dose is input from the linear ask. The present invention is applicable not only to beam radiotherapy machines but also to various types of radiotherapy machines such as rotary cobalt, betatron, and override type remote afterloading intracavitary irradiation machines.

Does high-speed calculation device 3 measure dose distribution? It is a device that performs calculations at high speed. The calculation results are displayed on the video display monitor 5 via the image memory and controller 4. Instructions from the operator are input from the keyboard 6, which has alphanumeric characters and functions. Character-only C
The RT display device 7 displays the contents input from the keyboard T and the contents output from the microprocessor 1. magnetic tape device sit, c
It is used to import all the data from the magnetic tape recorded on the T image, and prints and displays the printer 9Fi calculation results and optimal results as letters and numbers.

Plotter 1011 is used to output figures, especially isodose curves. The floppy disk device is used to store and read stored information, such as a program for reading the basic functions and operations of the device according to the present invention, and patient information. Furthermore, a graphic input device 12 is connected to the microprocessor 1 and is used to input information on the patient's body outline and anatomical organs, 2 information on the position of a radiation source inserted or injected into the body, etc. .

In Figure 1, the identification number of the patient undergoing radiation therapy is shown first.

Name, date of birth, and other diagnostic information and information regarding treatment strategies are entered into the microprocessor 1 in alphabetical characters, numbers, kana characters, etc. using the keyboard 6 and the character display CRT device 7. This information is output and stored on the floppy disk 11 as a patient file.

When treating a lesion within the patient's body by irradiating it from outside the patient's body, the graphic input device 12 inputs information such as the outline of the body, the position and shape of the lesion, and
Lung contours and bones as size and other anatomical data,
Input the position information of other clinically necessary force organs. The graphic input device 12 is also used to input information on the positions of these radiation sources photographed on film in a treatment method in which the radiation source is completely inserted or penetrated into the vicinity of the lesion within the patient's body.

A magnetic tape device 8t-jcTiii reads CT image data from the recorded magnetic tape and sends it to the processor 1. Processes the CT image sent from the magnetic tape device 8,
The anatomical information of the patient is converted into data as if it were input from the graphic input device 12. In other words, the body contour is extracted, and the density or Fi is extracted from the CT number matrix.
It is converted into a matrix of X-ray absorption coefficients and is useful for correcting density irregularities when calculating dose distribution. Using the device according to the present invention, the floppy disk device 11 must store in the processor 1 a dose distribution calculation program that differs depending on the type of treatment technique used. 2 to read the floppy disks provided one by one and send the program corresponding to the treatment technique to the processor 1.
One of the equations is used. The other set serves the same role as the magnetic tape device 8 by reading the patient file stored on the floppy disk and the floppy disk on which both CT images are recorded, as described above. Printer-9Fi Prints out all character information for effectively using the device according to the present invention, such as recording the results of automatic comparison of dose distribution.

As a result of automatic verification based on the dose distribution, the plotter 10
Alternatively, it is used to draw a dose distribution curve as a result of treatment. In this case, the graphic input device 12, the magnetic tape device 8, or the flash disk device ft1f1 is first installed.
It is also possible to draw an anatomical cross-sectional view of a patient input using one of the devices, superimposing it on the isodose curve.

The radiation therapy machine 2Fi, which is one of the important components of the present invention, sends to the processor 1 the treatment conditions during treatment that change at sampling intervals.

The high-speed calculation device 3 is the most important table component of the present invention,
Figure 2? Reference will be made later in detail.

Image memory and controller 4 #i receives and rewrites the coordinate data of the isodose curve as a calculation result from the high-speed calculation device 3 every time all calculations are completed.

On the other hand, an analog image signal is sent to the video monitor 5KJj at a fixed number of frames per second and displayed as an isodose curve. Note that anatomical information such as the patient's body contour inputted from the graphic input device 12 described above is directly transferred from the processor 1 to the image memory and controller 4 and written therein, so that it can be displayed superimposed on the isodose curve. I can do it. Also, 01 inputted through the magnetic tape device 8 or floppy disk device 11 described above
Image information is also directly transferred from the processor 1 to the image memory and controller 4, and is displayed in a superimposed manner with the CT image isodose curve. Since the CT image has a gray scale tube, this image memory also has a gray scale.

The hitio monitor 5 displays images sent from the image memory and controller. This image is the isodose curve calculated by the high-speed calculation device, and the graphic input device f
I entered it on i12. It is a figure in which the anatomical information of the patient is superimposed, and the above-mentioned CT image isodose curve is superimposed on the figure.

The automatic verification of treatment based on the lfM dose distribution according to the present invention is performed by the radiation therapy machine 21 processor 1. High-speed arithmetic unit 3. Image memory and controller 4. It is implemented in the components connected to the video monitor 5. A schematic flowchart of its implementation is shown in FIG. Input from radiation therapy machine 2, dose distribution calculation 2 display, input.

This is done by automatically repeating the cycle of g1 calculations. During this cycle, the isodose curve displayed by the radiation therapy machine 2 in response to changes in the treatment price that change every moment as the treatment progresses appears to move like a moving image.

The above is an explanation of each component of one embodiment of the present invention using a block diaphragm.Next, the high-speed arithmetic unit 3, which is an important component of the present invention, will be explained with reference to FIG. The present embodiment will be described below with reference to the schematic flowchart shown in FIG. 3, and then how the dose distribution calculation will be performed will be explained.

FIG. 2 shows an example of a high-speed calculation device which is the most important component of the present invention. The configuration shown in the figure is a dedicated device whose entire purpose is to perform high-speed calculations of dose distributions, and is not a device that performs ancillary calculations of a host computer like a simple general-purpose array processor.

In other words, it is a modularized series of processing methods. If this high-speed arithmetic device is a black box,
By providing anatomical map data such as body contour and treatment parameters for each patient to this black box, an isodose curve is displayed as a calculation result. These isodose curves are expressed as a 256×256 matrix in one plane and output as digital values. These digital values are once stored in the image memory, but the data is transferred from the image memory to the controller in the direction of the camcorder and displayed on the video monitor. The internal structure of the high-speed calculation device allows for versatility in irradiation techniques for dose distribution calculations, such as external irradiation that irradiates a lesion inside the patient's body from outside the patient's body,
Intracavitary irradiation, in which a radiation source is inserted or penetrated near the lesion in the body;
Also, it can be controlled by software in order to be adaptable to intra-tissue irradiation. That is, the device operates as firmware during operation, and is composed of detailed calculation modules so that it can be adapted to a plurality of line N calculation algorithms. The progress of the computation is determined by a microprogram within the arithmetic unit.

In FIG. 2, 31 to 40 indicate components in the 3ti high-speed arithmetic device. 31Fi high speed RAM, 32F
i low speed RAM, 33t/'i memory address controller, 3
4 is a RAM and ROM for storing programs, 35i1 program sequencer, 36ti program decoder, 37 is a floating point arithmetic module F'PU, 3B is a function arithmetic module, 39 is a central processing unit in this high-speed arithmetic unit, and the CPU 40 is a high-speed arithmetic unit. and an input/output interface I10 with external devices. The microprocessor indicated by 1 in the figure is the microprocessor shown in FIG. 41 is a parallel interface between the microprocessor 1 and the high-speed arithmetic unit 3. 4 is an image memory and controller (also shown in Figure 1), 5 is a video monitor (also shown in Figure 1), and 42 is a debugging console, which is used as part of the microprogram development tools. It is not used after the microprogram is completed. The reasons for dividing the RAM into high-speed RAM 31 and low-speed RAM 32 are to reduce cost, save power consumption, minimize heat dissipation, and increase mounting efficiency. A large amount of data that needs to be accessed many times is stored in a high-speed RAM 31, and conversely, data that requires a large amount of data area is used in a low-speed RAM 32. For example, in the case of irradiation from outside the patient's body, that is, external irradiation, ti
TAR (Ti5sue Air, Ratio ggl
/air pressure ratio) table, OCR (Off Con
ter Ra-tlo (off-axis line ratio), tables for correcting differences in internal density, etc., are stored in high-speed RAM3.
In addition to storing 6 frames (6,000 planes) of the dose distribution calculation results on the 164×64 matrix in the low-speed RAM 32, it is also used to store the patient's anatomical figure data. High speed RAM31 capacity 11jj 4
K bytes, the capacity of the low-speed RAM 32 is 128 bytes. Due to the calculation-based irradiation technique, the entire u12BK byte is not used, and the capacity is kept with a margin. Access time of high-speed RAM 31 is 120 n+s
, the access time Fi of the low-speed RAM 32 is 720 ns.

The EPU (floating point arithmetic module) 37t-J handles floating point values as 20 bits and fixed point values as 16 bits, and can perform the following operations. That is, converting fixed-point data into floating-point data, converting it in the opposite direction, converting only data below the decimal point into floating-point representation, and performing multiplication and addition/subtraction as floating-point operations.

yL calculation time for each function 240 ns for conversion between floating point and fixed point, 48 ns for floating point multiplication, addition and subtraction
It is 0ng.

The F"XU (function calculation module) 38 is a modular version of calculations required for data interbolation, which is sometimes required in dose distribution calculations.
x, log x, tan x, tan-1
The calculation function of x is poor, the execution time is Fi360nI! I
It is.

High-speed RAM31. Low speed RAM32. The decoding time of module instructions such as EPU (floating point arithmetic module) 37 and FXU (function arithmetic module) 38 is 120 ns, and the execution time in each of the above modules is added to this to obtain the instruction execution time. However, the instruction execution time for continuous operations such as writing data to high-speed RAM 10 times is (120 ns + 240 ns) because it enables p'lying operations.
) x 10 times (here 240 n5Fi high speed RAM write time), 120nss x 10 times + 240
ns = 1440 ns.

In order to perform all dose distribution calculations on this high-speed calculator, a microprogram is created using the high-speed calculation microcode and then executed.

An example of the algorithm for dose distribution calculation will be described later. A cross assembler using a large computer is used as a development tool to create microprograms. Here, the assembled microcode is written on a magnetic tape and read by the microprocessor 1 (which corresponds to a host computer from the perspective of the high-speed arithmetic unit 3) in the device according to the present invention. While executing the program, it is also stored in a storage medium such as the floppy disk 11, and read as necessary. The program storage ROM 34 in this high-speed arithmetic device 3 has a wake-up program necessary for starting the high-speed arithmetic device and a control program for the Depag console 42 stored in advance, and when the Depag console 42 is connected, the program is automatically stored. The debugging console control routine is now started. The debugging console 42 is necessary for debugging microprograms, and is used for RUN, HALT, one cycle execution, and RAM of this high-speed arithmetic unit.
It is possible to display the contents of the ROM memory, write data to the memory, etc.

This debug console will not be used once the dose distribution calculation microprogram is completed and Depag is removed, so it can be removed from the components of the present invention.

In a normal state where such a debug console is removed, this high-speed arithmetic unit 3H1 first waits for an instruction from the host computer, that is, the microprocessor 1. In other words, the mode is set to read data from the host computer. Between the two, there is a 1116-bit parallel input/output line and a simple control line for inputting and outputting the line, and they are connected to each other. That is, the CPU 40 and host computer 1 in FIG.
This is the input/output interface 41 that connects the microprocessor 1 with the microprocessor 1. This high-speed calculation device 3t-
To control from the outside, control commands are included in the 16-pit data string in a predetermined order.When the power is turned on, a data input request is sent to the high-speed processing device 3Fi host computer 1 via the l1041. flag. The host computer 1ij recognizes this and sends the data transfer word count to the high-speed arithmetic unit fi3, the start address of the program RAM storage in the arithmetic unit, the start address, the calculation program, and a table of constants necessary for calculation (the TAB described above).
, OCR, etc.) Transfers treatment parameters, calculation parameters, etc. specified by the dedicated input device 2. Then, the high-speed arithmetic unit fif3ti executes the above-mentioned up-up program, stores the transferred data at a predetermined address in the program RAM, and starts the up-down calculation program at the designated address. When the series of calculations is completed, this high-speed processing unit ft3Fi again sets a data input request flag to the host computer 1 and waits for input. Here, if any of the treatment parameters or calculation parameters specified with the dedicated input device 2 has been changed, the address where the treatment parameter is stored, the treatment parameter, the number of transferred words, and the start address are added and high-speed calculation is performed. Transfer to device 3. The high-speed calculation device 3 sets a data input request flag to the host computer 1 every time a series of calculations such as dose distribution calculation and output of the isodose curve to the image memory 4 is completed, and automatically repeats the dose distribution calculation. I'm going to go. The faster these series of calculations are performed, the faster the isodose curve displayed on the CRT 5 moves. When the microprogram in the high-speed calculation device 3 is activated and dose distribution calculations are started, these calculation results express calculation cross sections one after another6.
It is stored in the low-speed RAM 32 as a 4X64 matrix. In the scratch pad area of the RAM 32, for example, in the case of multi-field irradiation in the above-mentioned external irradiation, the total value of a plurality of amounts is stored. In the case of intracavitary irradiation, the total value of multiple sources is stored for the number of the ovoid source or tandem source. The calculation results on these 64x64 matrices are displayed in the raster direction of the video display monitor, for example, 2
The data are transferred line by line to the high-speed RAM 31, where the isodose curves are extracted by the interbolation method and sequentially transferred to the image memory 4. The transfer is compressed to 16 bits and handshaked in a busy/ready manner.

As described above, since this high-speed arithmetic unit 3 is based on a microprogram, it can be used for general purpose purposes by changing the microprogram itself, although within the constraints of server hardware. General purpose here means adaptability to dose distribution calculations for all treatment techniques as described above.

FIG. 3 is a schematic flowchart illustrating an example of the temporal order of execution of how automatic verification is performed according to the present invention. In the figure, first, the operator selects a task 401 to determine whether to perform automatic verification, or perform other tasks, such as having a plotter draw and output the results of automatic verification or treatment results, or printing out treatment conditions on a printer. Make work selections such as: When automatic verification is selected by the operator, an instruction 402 causes an automatic verification instruction to be issued from the operator console (consisting of 6 and 7 in FIG. 1). It is connected to the microprocessor 1 substantially online.

Next, at input 403, numerical values of parameters representing the treatment conditions and calculation conditions accompanying the progress of treatment of the radiation treatment machine 2 described above are input to the microprocessor 1. In the case of near radiotherapy, the numerical values of these parameters are as follows. In other words, in the case of multi-port irradiation, the gate number, the irradiation direction between them (gantry angle), the irradiation field size, the rotation angle of the X-ray head, the height of the treatment bed on which the patient is placed, the horizontal position, and the vertical position. These include the Gantt IJ rotation start position and stop position, dose rate, cumulative dose, etc. in the case of one-rotation irradiation. The types of these treatment parameters also vary depending on the type of treatment machine and the irradiation technique used.

The range of numbers also changes. The value of this parameter is displayed 40
4 and is displayed on the operator console, specifically, the character-dedicated CRT display device 7. This operation 404 is performed almost the same as the operation 403.

Next, the operation of the high-speed arithmetic operation 405, that is, the high-speed arithmetic unit 3 inputs the data from the dedicated input device 2 to the host computer 1 as described above.
Dose distribution calculations are performed based on parameters representing treatment conditions and calculation conditions sent through 'ft-, and isodose curves are extracted as described above. Once that is finished, transfer 4
The isodose curve is transferred to the image memory 4 as shown in 06.

The contents of the image memory 5 are repeatedly displayed on the video display device 5 in the same way as on a normal television monitor, so when a new isodose curve is written in the image memory 4, the isodose curve displayed on 5 is new from that moment. Become something. The repetition of steps 406-408 occurs independently of the advance from step 406 to step 407.

The operation 407 performed after 40B is the radiation control device 2.
This is an operation to check whether the treatment has been completed. As mentioned above, when the radiation dose distribution for a certain patient is exactly as planned, the treatment is completed.
When this is detected, the process returns to step 401 and executes a routine that outputs the optimal dose distribution on a plotter or outputs the corresponding treatment condition parameters on a printer.

However, if the dose distribution according to the plan is not obtained yet, that is, if the dose distribution map is not yet the same as the plan when viewing the dose distribution map on the video device 5, the treatment will not be completed and the procedure 403 will be automatically performed. Get into action.

Then, the operations 403 to 407 to 403 to 40 γψΦ· are repeatedly circulated. This circulation cycle will be referred to as an automatic verification cycle.

Next, is there an example of the dose distribution calculation method that has often appeared in the examples described so far? state Methods for calculating dose distributions have been published in numerous papers and books not only overseas but also domestically. The basic theoretical formula is well known, and various methods for increasing calculation accuracy and speed have been published in various papers and are well known. The present invention has also been made with various devices. In other words, they include improvements to the order of calculations in order to minimize the amount of memory occupied and to increase calculation speed.

However, the feature of the present invention is that any calculation method can be implemented by replacing it with a program, so we will select and describe an embodiment that best suits the present invention from among the calculation methods that have already been published. I'll decide. Calculation methods other than those described in the embodiments described herein can be implemented by the present invention as long as they are not fundamentally different.

That is, it can be implemented by creating such a program and executing the program using the method 2 described above.

First, an embodiment of a dose distribution calculation method for so-called external irradiation, in which X-rays, R-rays, etc. are irradiated from outside the human body and absorbed into lesions for treatment, will be described. This example is based on what is described in the following book.

Published by Butterworths+ Publisher 1974, C
om-puterg in Mediain@5e
ries (Qene-ral [Dditior:
One of the series by D, W, Hill) - Com
puters: in Radiothe-rapy p
R, G, W in physical aspects'
- written by ood. Among these, first P,
1 to R6 (::hapterj, Introdu
This article describes the characteristics of the basic data and measurement data that are the raw materials for conducting the dose distribution meter xi.

It also describes what the isodose curves obtained as the calculation results are. Next, P, Ch from 7
apter 2. Some Theoretical
In Con5iderations, in this example, the above-mentioned L7 T A R (Tl5iue Air
Ratio), such as Percen
[page pepth])ose, the physical background thereof is described, and the definition is clarified. From the middle of page 15, we will discuss how to express TAB of high-energy X-rays and r-rays using empirical formulas, and discuss the TAB and 8A mentioned above.
The relationship of R (5catter, Air 1Zatio) leads to calculation of dose distribution by SAR on page 16. Then, on page 19, equation (2.19) and (2
@20) Formula? The sum becomes the calculation formula. ch-apter3. on page 21. From Dep on the beam center axis
th Dos-e Curvg expression method 2
In this embodiment, the above-mentioned 0CR (Off Center)
After describing the correction method when the irradiation field is not square, Mr. vande Gefjn and pfal
It describes the calculation method for single irradiation using the formula derived by Mr. Zner.

From the second half of page 34 onwards, a method of expressing calculations on a calculation cross section is described, making full use of the IJ system, which is unique to computer calculations. Four methods are listed as specific examples, and the last method, the Tronto program, describes in mathematical formulas how to handle wedge filters and how to increase irregular irradiation. Chapter 5 from page 64
．． This article describes how to combine and calculate the Vi1 gate irradiation resistance for multiple gate irradiation with two or more gates and rotational irradiation. Two specific examples are given.

Then, as the isodose curve of the synthesized dose distribution, CRTK
Although it describes how to display it with a specific example,
As one example, P. 79 also describes an implementation method that the inventor of the present invention conducted for eight years.

The references cited are detailed in this pamphlet.

Next, an example of dose distribution calculation for electron beam irradiation in external irradiation will be described. Even in the case of electron beams, it is possible to apply the contents of the above-mentioned book by R.G. and Wood for X-rays and r-rays as is, but since it is disadvantageous in terms of calculation accuracy and range of application, the present invention does not apply it. It was carried out in different ways. The calculation method is described in detail in the following two papers.

One of them is PHYS, MED, BIOL, 1979V
o124. No. 2299-309 (Printed
%Bet on 1nGrent Br1tain)
atron Elcc-tron Beam Char
aeterizatlon for Dosimeter
Job-n D is famous for y Calcation'.
,5tebon,N,Ayyangar,N,Thun
t-haralingam.

Kono paper is P, 30o, 2. As stated at the beginning of Method, this describes how to apply Mr. Kawach's method to betatron electron beams.
chi Q's paper Fi July 1977 Na-
tional In+5 orientation of R
ad%logical Sciences Anaga
A report issued by wa Chiba Japan *'EXpe-dient with NlR8-1<, -6
(:alculation Methods of
5p-atial Dose Distrib
tion of ,tightEnergy C
Harged Particles' (Study on a method for calculating the spatial dose distribution of high-energy charged particles). This method can also be applied to calculations of irradiation with proton beams.

Next, the dose distribution calculation method for intracavitary irradiation and intratissue irradiation is specifically described on pages 48 to 63 of the book by R.G. Wood mentioned above.

This Chapter 4. In addition to the calculation method for lighting a single radiation source or a single radiation source, the content specifically describes seven synthesis methods for cases where multiple radiation sources are inserted or penetrated.

In the present invention, as described in the embodiment of the dedicated input device 2, it is also possible to calculate the case of intracavity irradiation using the override method or the morte afterloading, but this book by R.G. , 59-4゜2.3. Programs for Afterlo
adingl)evices only describes the non-overriding method. However, in the case of the override method, the source intensity at each override position.

It can be easily calculated by considering one set of irradiation conditions, including position coordinates and irradiation time, as irradiation conditions by one radiation source.

Furthermore, although it is not possible to calculate the dose unless the absolute position of the radiation source inserted into the body is known, as mentioned briefly in the explanation of the graphic input device 12 in the explanation of the embodiment shown in FIG. A photographic film of the body into which these radiation sources have been inserted or penetrated, taken from two perpendicular directions, top and bottom and left and right? This is realized by placing the positions on the tablet 12 and inputting the positions of these radiation sources to the microprocessor 1 using a tablet. In addition to scanning in two directions at right angles, it is also possible to read the entire source position from photographic film taken in stereo, but in this case,
The program for input is a different algorithm.

Next, regarding dose distribution calculation in the case of irradiation using a combination of external irradiation and either intracavitary irradiation or interstitial irradiation, see the procedures of the Var.
ian C11nac Users Meeting
May31- June 2, 1978 San
Diego Calif.

%Advances in the
Integration of Extern
al Beams and E-ndocurie
The paper entitled Therapy I was published at Univ-ers.
ity of 5outhrn Cal1forn
ia, F of 5c-hool of Mediains,
W., George I et al., and the present invention implements this content.

Furthermore, the present invention implements the following as a treatment plan using 07 images. That is, firstly, in the dose distribution calculation of external irradiation using the aforementioned irradiation techniques (for example, XM, rM), the magnetic data divided by MT+ is interpreted as 8!/L in Figure 1 for both CT images. It is possible to read MT using a CT device made by any manufacturer by knowing the file format of the image data.Secondly, by copying such image data to a floppy disk through the floppy disk device 11, This allows the MTt managed by the CT device to be returned immediately and prevents damage or loss, while also having the advantage of being able to manage OCT images around the device using a floppy disk according to the present invention. Thirdly, while looking at the CTi1jRun' displayed on the video display 5, you can input instructions for the center of the lesion to be irradiated, the gantry angle, etc. from the graphic input device 12, so that the anatomical shape inside the body can be input. It is possible to input clinical instructions while knowing the

Fourth, the body contour is automatically extracted by executing a program using both CT images. These figure input devices 12
It is possible to eliminate the need to input body contour figures one by one. The fifth step is to obtain the electron density matrix from the data expressed by the entire matrix of CT numbers of both CT images, and perform heterogeneity correction calculations. Sixth, it is possible to superimpose and display isodose curves as the calculation results of both CT images on the screen of the CRT 5, and to compare the detailed CT tomographic height of the anatomical form and the dose distribution. . 1st and 4th excluding the 2nd and 3rd among the above. The fifth and sixth matters are already known and described in the papers listed below.

(1)%Cl1ml Application
of aCT based treatment
nt Planning System' by Ma
re R, Sontag and J, R, Cunni.
ngham, Computed Tom-ograp
hy vol, 2. pp 117-130 Pe
-rgamon Press+ Ltd, 1978
Pr1nt-ed in Qreat Bitai
n+21' Dosimetric Evalna
tion ofa ('computed Tomog
raphy Treatment System
' by 5atish (', pr-asad Q
lenn P, Glasgow and Jam-e
s A, Purdy, Radiology 1
30 Near 77-781 March 1979+31
% potentials of Compute
ted To-mography in Radi
ation 'l'therapyTreatment
Plannlng' by IEdw-in
C.McCullough, Radiol
ogy129 near 65-768, peeemb
er 1978 (4: % The 1icqu
ivalent Tl5sue-AlrRatio
Method for Making Abs
Orbed Dose (:alculatto
n in He-rogeneons Medi
um' by MarcR, Sontag
and John R, Cunnling-ham.
, Radiology 129 Near 87-7
87-794Dece 1978 (5) %Computed Tomograpb
y Appl 1-ed to Radioth
erapy Treatment Plannlng
: 'l'echniques and RR
e-5ult' by Pan1ine)
lobday.

Ne1l Hod8on, Jan@t H
usband.

Roy P, Parker and James
S, Mac-donald, Radiol
ogy 113:477-482, No'v
ember 1979 (6) % Tbree
Dim*ntloned ModelPlannin
g' by 8teven L, Fr1t8I
WEE 1979, CH1404-3/79
10000-0061 $00.715 (7)%An Interac mouth ve Treatme
ntPlanning Using Compute
ed Tomo-graphy for Int
racavltary Rad-1otherapy
: by Kyo Rak Shil.

W 11am H, Anderson, SRnwe
llJ, Dwyer I, Ho1
lace L, COX.

Cal M, Mansfield, Errol
Levln-e and, Arch W, Templ
eton IEEE1979 GH1404-3/
7910000-0056$00,7B 181' Localization ln
Interstit-1al Dosimetry
Utiling the CTSaanna
' by Arnold Herskov-1c
, Tbomas N., Padical and.
Sa-ng N,'[,es,Computed
Tomograph-y vol, 3,
pp 101 to 103Magnetic
Tapes for Exchange! n-g
the CT Image information
ion 1 (magnetic tape mutual conversion and display for CT information exchange) by Massaoml 'l'ak1z
awa (Tears Masaomi), Toshio Kobay
ashi (Toshio Kobayashi), Kiyoahi Maru
yama (Kiyoshi Sakiyama), Keiato Yano
(Yano Asato), and Emechi 'l'al
(ensika (Sakae Takenaka)) You should be able to tell which of the above-mentioned 1st, 4th, 5th, and 6th implementations the documents (1) to (9) above were used for by looking at the title of the document. There are also papers that contribute to the realization of multiple items among items 1, 4, and 5.

Next, the fourth method of extracting body contours was carried out with particular reference to the following literature.

r+or Contour extraction of RI images" Video information (M) January 1980 issue (Kurama, Shimizu, Takenaka, Nakatani) ++1) r Heart contour extraction from chest X-ray images" Video information (M) April 1980 issue (for Hase) , Toriwaki) The effects shown in the above examples will be summarized and briefly described. First, in the case of external irradiation as described above, the C1 image is displayed on the video monitor 5, and the anatomical or morphologically detailed cross-sectional view is superimposed on the same screen and displayed. Since an isoline curve is expressed as a calculation result considering the figure or shape map as information for a1 calculation (for example, using the result of contour extraction), an extremely clinically advantageous effect is achieved. Moreover, as a synergistic effect, the treating doctor can see the curve move on the video monitor 5 like a slow-motion picture with a slight time delay, such as +ff14, which corresponds to changes in treatment parameters as the treatment progresses due to irradiation from the radiation therapy machine to the patient. Since the detailed information expressed by the C1 image is displayed, an excellent clinical effect can be obtained by comparing it with the detailed information expressed by the C1 image. For example, a high-dose isodose curve of 90% or more covers the lesions that can be determined from the C1 image as much as possible to help remove the lesions, and a low-dose isodose curve of 305A or less is visible in the C1 image. Maybe it's a side effect of radiation? The automatic verification cycle shown in FIG. 3 can be carried out while visually confirming that the target organ is easily detected.

Similar effects can be obtained with irradiation methods other than external irradiation, such as intracavitary irradiation.

As explained above, the present invention is a high-speed arithmetic device.

Radiation source N machine 1 image memory etc? In addition to the conventional dose distribution calculation device, the high-speed calculation device has one plane (Ii!11
I use a dose distribution meter (for one frame) repeatedly at high speed and display it on a CRT. During the repeated cycles, the calculation results corresponding to continuous changes in the treatment extension as the treatment progresses with the radiation therapy machine are displayed as a slow-motion video of the isodose curve, allowing the treating physician to Is it possible to automatically check whether the dose distribution according to the optimal treatment plan has been obtained? It is something that you have.

[Brief Description of the Drawings] Figure 1 is a block tiageram showing the configuration of an embodiment of the automatic dose distribution matching device for radiotherapy according to the present invention, and Figure 2 is the high-speed calculation device shown in Figure 1. Internal structure of embodiment 3? The block diagram shown in FIG. 3 is a flowchart illustrating an example of the operation of the apparatus according to the invention. 1...Microprocessor (host computer) 2...Radiotherapy machine (e.g. linear disk) 3...High speed calculation unit 41...Image memory and controller 5@φ Video display monitor 6@...Keyboard 7...・・CRT display equipment 8・・Magnetic tape device 9*e・Printer 10・・Plotter 11・・Floppy disk device 12・・Graphic input device 31・・High speed RAM 3211・Low speed RAM 33・・Memory address controller 34.-RAM and ROM35 for program storage...-
Program sequencer 36...Program decoder 37'1/Floating point arithmetic module FPU38...
Function calculation module 39... Central processing unit in high-speed calculation unit 4.0... Input/output interface l
1041・Φ・Parallel interface 42...Tehagu console 401...Business selection (e.g. plotter output) 402・
・Operator console automatic verification section instruction (this makes the radiation therapy machine work)
6403... Input from radiation therapy machine (parameter changes due to treatment progress) 404... Digital display of input parameters (operator console display) 405... High-speed calculation (including isodose curve extraction) 406
...Transfer to image memory 407 ...End of treatment 40B ...Video equipment M5

Claims (1)

[Claims] An input device for inputting treatment status or treatment parameters as data or numerical values during treatment of a patient with a radiation therapy machine, and an input device that repeatedly calculates the data or numerical values from the input device at high speed and changes over time. It includes a high-speed calculation device that calculates the absorbed dose distribution in the patient's internal body space, and an output device that superimposes the output of the high-speed calculation device on the patient OCT image or the internal anatomy diagram and displays it as a moving image. An automatic dose distribution verification device for radiation therapy configured to quantitatively display the situation as a temporal change in the absorbed dose distribution in the body, thereby allowing a treating physician to verify the treatment plan and treatment progress.