JP2012073192A - Device and method for measuring radiation source intensity - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation source intensity measuring device for efficiently measuring an intensity of a radiation source to be inserted into an affected area, and a radiation source intensity measuring method thereof, and to provide a device and method for measuring the radiation source intensity capable of detecting mix-up in radiation sources.SOLUTION: The radiation source intensity measuring device for measuring an intensity of a radiation source includes a computer 33 having a storage unit that stores a measurement parameter for each position to be inserted with a minute radiation source of a minute radiation source inserting device 1; and a radiation sensor 31 for measuring the intensity of radiation from the minute radiation source which is moving in a guide needle 21 of the minute radiation source inserting device 1. The computer 33 specifies a stored measurement parameter based on the insertion position, and detects the intensity of the minute radiation source based on the specified measurement parameter and the radiation intensity measured by the radiation sensor 31.

Description

  The present invention relates to a radiation source intensity measuring apparatus and a radiation source intensity measuring method capable of measuring the intensity of a radiation source when the radiation source is inserted into a human body or the like.

  Sealed brachytherapy (brachytherapy) is a treatment that kills cancer by administering a high dose only to the tumor by permanently inserting (indwelling) the radiation source into the cancer tissue. This treatment has been applied to tongue cancer, prostate cancer, cervical cancer, and the like.

  For example, in the treatment of prostate cancer, about 80 to 100 radiation sources are permanently inserted into the affected area, and the surrounding cancer cells are destroyed and killed by radiation to treat the cancer.

  The intensity (dose rate) of the radiation source inserted into the cancer tissue is supplied with a certain accuracy from the manufacturer, but in reality, a radiation source deviating from the standard value may be included. When such a radiation source is permanently inserted, the expected effect may not be obtained.

  For this reason, the dose (intensity) of each radiation source is measured before inserting the radiation source into the affected area. If the dose is too high (too strong), the distance between the adjacent radiation sources is increased and the dose is reduced. If it is too weak (too weak), an action such as inserting an additional radiation source in the vicinity is desired.

However, the operation of measuring the intensity of the radiation source to be inserted one by one using a normal measuring instrument takes time and is inefficient. For this reason, a technique for efficiently measuring the intensity of the radiation source to be inserted is required.
Further, in the method of measuring the intensity before insertion, even if a radiation source is mistaken after the measurement, the fact cannot be detected. For this reason, there is a need for a technique that can easily detect the fact that a radiation source is mistaken.

Examples of techniques for efficiently and accurately measuring the intensity of radiation include those described in Patent Documents 1 to 3. However, the techniques described in Patent Documents 1 to 3 are techniques suitable for measuring the radiation dose of a large facility or apparatus, and the apparatus is large and complex, and efficiently measures a large number of minute radiation sources. Inappropriate for
In addition, these techniques cannot detect a mistake in a minute radiation source.

JP 2007-333463 A JP 2002-365268 A JP 11-337648 A

The present invention has been made in view of the above circumstances, and an object thereof is to provide a radiation source intensity measuring apparatus and a radiation source intensity measuring method capable of efficiently measuring the intensity of a radiation source for inserting an affected part. To do.
Another object of the present invention is to provide a radiation source intensity measuring apparatus and a radiation source intensity measuring method capable of detecting a mistake in radiation sources.

In order to achieve the above object, a radiation source intensity measuring apparatus according to the first aspect of the present invention comprises:
A device for measuring the intensity of a radiation source when inserting the radiation source into an affected area,
A storage unit for storing measurement parameters for each insertion position;
When inserting the radiation source into the affected area, a measurement unit that measures the intensity of the radiation from the radiation source moving along the guide,
The measurement parameter corresponding to the insertion position of the radiation source is identified from the measurement parameters stored in the storage unit, and the radiation source intensity is determined based on the identified measurement parameter and the radiation intensity measured by the measurement unit. A control unit for obtaining
It is characterized by providing.

  For example, the measurement parameter includes a measurement sampling period, the number of measurement values to be employed, and a coefficient for obtaining the intensity of the radiation source from the measurement values. In this case, for example, the measurement unit performs measurement at a sampling period specified by the measurement parameter, and the control unit records a series of measurement values acquired by the measurement unit, and records the recorded measurement values. The number of measurement values specified by the measurement parameter is extracted from the inside, and the intensity of the radiation source is obtained based on the extracted measurement value and the measurement parameter.

  For example, the measurement unit has directivity and has a certain measurement area in which radiation from a radiation source can be appropriately measured, and the control unit is configured to select the radiation source from a series of stored measurement values. The measurement value measured when is in the measurement area is extracted.

  The measurement parameter is desirably set to a numerical value based on the maximum moving speed of the radiation source when the radiation source is inserted into the affected area, so that the intensity of the radiation source can be obtained even when moving at the maximum moving speed. .

  A notification means for performing a predetermined notification may be arranged when the strength obtained by the control unit and a predetermined planned strength satisfy a predetermined standard.

  For example, the measurement parameter is obtained by moving a calibrated radiation source having a known intensity along the guide for each insertion position, measuring the intensity of the radiation from the calibrated radiation source, Including those obtained from the intensity of the calibrated radiation source.

  In order to achieve the above object, a radiation source insertion device according to a second aspect of the present invention includes the radiation source intensity measurement device.

Furthermore, in order to achieve the above object, the radiation source intensity measuring method according to the third aspect of the present invention is:
A method of measuring the intensity of a radiation source when inserting the radiation source into an affected area,
Obtain measurement parameters for each insertion position,
Measure the intensity of radiation from the moving radiation source toward the affected area at the time of insertion,
Identify the measurement parameter corresponding to the insertion position, and determine the intensity of the radiation source based on the identified measurement parameter and the measured radiation intensity.
It is characterized by that.

Furthermore, in order to achieve the above object, a computer program according to the fourth aspect of the present invention provides:
On the computer,
Processing to store measurement parameters for each position where the radiation source is inserted into the affected area,
A process of recording the measurement results of a measuring device that measures the intensity of radiation from a moving radiation source for insertion into the affected area;
A process for determining the measurement parameter based on the insertion position, and determining the intensity of the radiation source based on the specified measurement parameter and the recorded radiation intensity;
Is executed.

  According to the present invention, since the intensity of the target radiation source to be inserted into the affected part is measured, the intensity of the radiation source can be efficiently measured in parallel with the insertion process. In addition, since the intensity of the radiation source being inserted is measured, it can be easily detected when a mistake occurs.

It is a figure which shows the structure of the radiation source insertion apparatus which concerns on embodiment of this invention. It is a figure which shows the structural example of the template shown in FIG. It is a figure which shows the structure of the insertion apparatus shown in FIG. 1, (a) is a state which the source cartridge separated, (b) is a figure which shows the state which mounted | wore with the source cartridge. It is a figure which shows the structure of a minute radiation source. It is a block diagram which shows the structure of a measuring apparatus. It is a figure which shows an example of the parameter table arrange | positioned at a computer. It is a figure for demonstrating a measuring method. It is a schematic diagram which shows an example of the state during operation. It is a flowchart for demonstrating the radiation source intensity | strength measurement process which a computer performs. It is a figure which shows the example of the measured value obtained by one measurement (insertion of one minute radiation source). (A)-(c) is a figure explaining the example of a work table produced | generated by a radiation source intensity | strength measurement process, and a production | generation process. It is a flowchart for demonstrating the operation | movement which sets a parameter table. It is a figure which shows the example of the measured value obtained by moving a calibrated minute radiation source at predetermined speed. It is a figure which shows the other example of the measured value obtained by one measurement (insertion of one microradiation source). It is a figure which shows the modification of the parameter table memorize | stored in the memory | storage part.

  Hereinafter, a radiation source intensity measuring device and a radiation source intensity measuring method according to an embodiment for carrying out the present invention will be described with reference to the drawings based on an example in which the radiation source intensity measuring method is applied to a minute radiation source insertion device for prostate cancer.

  The micro radiation source insertion apparatus 1 according to the present embodiment has a function of automatically measuring the intensity of a micro radiation source to be inserted when the micro radiation source is inserted into the prostate (affected part). As shown in FIG. 3, the main body 10, the insertion tool 20 for inserting the minute radiation source into the affected part, and the radiation from the minute radiation source moving in the insertion tool 20 are measured to determine the intensity of the minute radiation source. Part 30.

  The main body 10 and the insertion tool 20 basically have the same configuration as the conventional one, and the main body 10 includes a support portion 11, an ultrasonic probe device 12, and a template 13.

  The support part 11 is a rod-like or plate-like member that supports the whole, and is installed on a support stand / stage or the like that can be adjusted in height.

  The ultrasonic probe device 12 is placed on the support portion 11 and has a rod-like shape in which the ultrasonic probe 12a is disposed at the tip portion. As illustrated in FIG. 8, the ultrasonic probe device 12 is inserted into the rectum from the anus of a patient whose distal end portion is in the lithotripsy position at the time of surgery. An ultrasonic probe 12a is disposed at the distal end of the ultrasonic probe device 12, and the ultrasonic wave is emitted from the ultrasonic probe 12a and the reflected wave is measured. Etc. are output as images.

  As shown in FIG. 2, the template 13 shown in FIG. 1 is a plate in which a plurality of position reference holes 13a for defining the position where the microradiation source is inserted into the body is formed. ing. As shown in FIG. 8, the template 13 is pressed against the perineum of the patient in the lithotripsy position at the time of surgery, and a guide needle 21, which will be described later, passes through one of the position reference holes 13a and is inserted into the affected area of the patient. Is done. The microradiation source is not inserted at all positions where the position reference hole 13a is formed, but the position where the microradiation source is inserted is determined according to the patient's condition, and the position reference hole 13a at that position is determined. Is used.

  On the other hand, as shown in FIG. 3A, the insertion tool 20 shown in FIG. 1 includes a guide needle 21, an applicator 22, and a radiation source cartridge 23 attached to the applicator 22.

  The guide needle 21 is made of a metal that transmits radiation, such as a titanium alloy or stainless steel, and has a passage (through hole) having a diameter of about 1 mm through which a minute radiation source passes. In this way, the template 13 is inserted until it passes through the position reference hole 13a and the tip of the template 13 reaches the affected area of the patient.

  As shown in FIG. 3A, the applicator 22 includes a mounting unit 24 to which the radiation source cartridge 23 is mounted, and an operation unit 25 that is manually operated by a user (a doctor such as a urologist). As illustrated in FIG. 3B, the radiation source cartridge 23 is mounted on the mounting portion 24. The operation unit 25 pushes the minute radiation source 26 built in the radiation source cartridge 23 mounted on the mounting unit 24 into the affected part of the patient through the guide needle 21 in accordance with the operation of the user.

As shown in FIG. 4, the microradiation source 26 includes, for example, a capsule 26a such as a titanium alloy having a diameter of about 0.8 mm and a length of about 4.5 mm, and a short half-life, low energy nuclide (for example, enclosed in the capsule 26a) , ¹²⁵ I, ¹⁰³ Pd) 26b.

  The measurement unit 30 shown in FIG. 1 is a device for measuring the intensity of radiation emitted from the microradiation source 26 while the microradiation source 26 is moving in the guide needle 21. The measurement unit 30 includes a radiation sensor 31 attached to the main body 11, a signal processing circuit 32, and a computer 33.

  The radiation sensor 31 is composed of, for example, a NaI scintillation measuring instrument, and measures the amount of radiation emitted from the minute radiation source 26 in the guide needle 21 at a predetermined sampling period, and outputs a measurement value. The radiation sensor 31 has a plurality of sampling periods and can be switched by a control signal from the computer 33. In addition, the radiation sensor 31 has a certain degree of directivity, and in this embodiment, the radiation sensor 31 has directivity in the front direction (the direction of the guide needle 21).

  The positional relationship between the radiation sensor 31 and the minute radiation source 26 is such that the position of the guide needle 21 (the position of the position reference hole 13a of the template 13 into which the guide needle 21 is inserted) and the position of the minute radiation source 26 within the guide needle 21. It changes according to. The radiation sensor 31 obtains a correct measurement value of radiation when the minute radiation source 26 is located in a predetermined range (measurement area S) substantially in front of the radiation sensor 31 (direction of directivity).

  As shown in FIG. 5, the signal processing circuit 32 includes an amplifier 321 and an A / D (analog-digital) converter 322, amplifies the output signal of the radiation sensor 31 according to the control of the computer 33, and performs A / D The data is converted and supplied to the computer 33.

The computer 33 is configured by a personal computer or the like, and includes a control unit 331, an input / output I / F (interface) 332, a storage unit 333, an input unit 335, a display unit 336, and a sound emitting unit 337.
The control unit 331 is configured by a processor or the like, controls the radiation sensor 31 and the signal processing circuit 32, takes in the output signal of the radiation sensor 31 via the signal processing circuit 32, and will be described later with reference to FIGS. Radiation source intensity measurement processing and measurement parameter setting processing are executed.
An I / F (interface) 332 transmits and receives signals between the control unit 331 and an external device. Specifically, the I / F (interface) 332 supplies a control signal from the control unit 31 to the radiation sensor 31 and the signal processing circuit 32, and supplies measurement data output from the signal processing circuit to the control unit 331.
The storage unit 333 includes a RAM (Random Access Memory), a hard disk device, a flash memory, and the like, and functions as a work memory for the control unit 331. The storage unit 333 stores a computer program for the control unit 331 to execute a radiation source intensity measurement process and a measurement parameter setting process which will be described later with reference to FIGS. 9 and 12.

  Further, the storage unit 333 stores a parameter table 334 illustrated in FIG. The parameter table 334 measures the identification numbers of the plurality of position reference holes 13a formed in the template 13 and the strength of the microradiation source 26 when the guide needle 21 is inserted through the position reference holes 13a. And measurement parameters for storing them in association with each other.

  Each measurement parameter includes a measurement sampling period, the number of data used for specifying the intensity of the microradiation source 26 (number of samples), a coefficient for obtaining the intensity of the microradiation source 26 from the measurement value (radiation intensity), and the like. .

  These measurement parameters can be appropriately measured under any conditions in consideration of fluctuations in the distance D between the radiation sensor 31 and the minute radiation source 26, fluctuations in the moving speed of the minute radiation source 26, and the like. Measurement parameters designed to be

Specifically, since the position of the radiation sensor 31 is fixed, the distance D between the radiation sensor 31 shown in FIG. 7 and the guide needle 21 to which the micro radiation source 26 to be inserted is conveyed is the insertion position, that is, the use. It changes according to the position reference hole 13a to be performed. In general, the radiation dose (measured value of the radiation sensor 31 (count number C)) is inversely proportional to the square of the distance D from the minute radiation source 26 (C∝1 / D ² ). Therefore, it is necessary to adjust the conversion from the measured value to the source intensity as the distance D changes. Further, the radiation sensor 31 can appropriately measure radiation only when the minute radiation source 26 is located in a predetermined range (measurement area) S substantially in front of the radiation sensor 31. However, there is a difference depending on the user and it cannot be specified at what timing and for how long the minute radiation source 26 is located in the measurement area S. However, the conveyance speed is usually 5 cm / second to 20 cm / second. In general, when the conveyance speed is low, measurement is easy, but accurate measurement becomes difficult as the conveyance speed increases. Therefore, it is necessary to set measurement parameters so that accurate measurement is possible even at a conveyance speed of about 20 cm / second. Further, the radiation count number C is scheduled to have an error of about ± √C. For this reason, it is necessary to secure a sampling period and the number of samples to some extent to suppress errors.

  The measurement parameters set in the parameter table 334 are values designed in advance so as to satisfy these conditions. A specific method for setting measurement parameters will be described later.

  Next, the operation of measuring the intensity of the micro radiation source 26 while inserting the micro radiation source 26 into the affected area of the patient using the micro radiation source insertion apparatus 1 having the above configuration will be described with reference to the flowchart of FIG. .

  First, in the same way as when inserting a normal microradiation source, a tomographic image of the affected area of the patient is used to determine at which position and in what order the microradiation source 26 is inserted.

  Next, the reference position hole 13a of the template 13 used for inserting the minute radiation source 26 at the determined insertion position is specified. In this example, for easy understanding, the 001th reference position hole 13a, the 007th reference position hole 13a, the 024th reference position hole 13a. . . The nth reference position holes 13a are used in this order. Next, as illustrated in FIG. 11A, a work table including the identification number of the specified reference position hole 13 a is registered in the storage unit 333.

  Subsequently, the user inserts the guide needle 21 into the 001th reference position hole 13a, and further inserts the guide needle 21 into the affected area of the patient. The depth of insertion can be confirmed by the ultrasonic probe device 12 or the like.

  The user instructs the computer 33 to start measurement and inputs the identification number 001 of the position reference hole 13a used.

  Subsequently, the user attaches the radiation source cartridge 23 to the attachment part 24 of the insertion tool 20, operates the operation part 25, moves the minute radiation source 26 in the guide needle 21, and inserts it into the affected part of the patient. .

  On the other hand, the computer 33 (the control unit 331) executes the operation program stored in the storage unit 333 in response to the measurement start instruction and the input of the identification number 001 of the position reference hole 13a, as shown in FIG. The radiation source intensity measurement process is started. First, the measurement parameter of the 001st entry is read from the parameter table 334 (step S11). For example, in the case of FIG. 6, the sampling period is 30 ms, the number of samples is 3, and the coefficient is 1.02.

  Next, the control part 331 sets the sampling period of the radiation sensor 31 according to the operation parameter read at step S11 (step S12). In this example, it is set to 30 ms. The radiation sensor 31 measures the radiation dose at the set sampling cycle.

  The control unit 331 sequentially takes the measurement values supplied from the radiation sensor 31 and stores them in the storage unit 333 (step S13). The control unit 331 repeats this operation until it is determined that the insertion operation has been completed (step S14; Yes). The end of the insertion operation can be determined, for example, when a relatively small measurement value continues for a plurality of sampling periods after the count number C has once increased.

During this time, the user operates the operation unit 25 to insert the minute radiation source 26 through the guide needle 21 into the affected part of the patient.
Accordingly, the relationship between the time and the measured value as illustrated in FIG. 10 is recorded in the storage unit 333.

  Next, the computer 33 specifies a value acquired during a period in which the minute radiation source 26 is located in the measurement region S (step S15). The specific method is arbitrary. For example, a maximum value (peak value) of measured values is specified, and a series of measured values having a value of 90% or more of the peak value and continuous sampling timing are obtained. The value acquired during the period in which the minute radiation source 26 is located in the measurement area S is specified. In the example of the data in FIG. 10, values P1 to P5 that have a value of 90% or more of the peak value P2 and the sampling timing continues are values acquired during the period in which the minute radiation source 26 is located in the measurement area S. Identified as

  Next, measurement values are extracted from the specified measurement values by the number of samples specified in the measurement parameters (step S16). At this time, the number specified by the measurement parameter is extracted from the measurement values specified to be values measured during the period located in the measurement area S. In this example, since 3 is set as the number of samples, three out of five are extracted. For example, three of P2 to P4 are extracted except for the first and last ones. The three to be extracted are data with continuous sample periods.

  Next, an average value of the three extracted measurement values is obtained, and this average value is multiplied by a coefficient k in the measurement parameter to obtain the intensity of the minute radiation source 26 as k · average value (step S17). In this example, the average value is multiplied by a coefficient of 1.02.

  Next, it is determined whether or not the difference (error) ΔI between the obtained intensity (actually measured intensity) I and the nominal (rated) intensity of the minute radiation source 26 is within a preset allowable error (step S18). . The allowable error is arbitrary, but can be set to about ± 10%, for example.

  When the error ΔI exceeds the allowable error (step S18; No), the control unit 331 drives the display unit 336 and the sound emitting unit 337 to warn of an abnormality (step S19). At this time, a notification is given so that it can be understood whether the actually measured intensity is larger or smaller than the nominal intensity and how much the error ΔI is. The doctor refers to the contents of the notification. For example, when the strength of the inserted microradiation source 26 is smaller than the nominal value, the doctor inserts another microradiation source 26 at an adjacent position, or communicates with the adjacent microradiation source 26. Processing such as closing the interval can be performed. Moreover, when the intensity | strength of the inserted microradiation source 26 is larger than nominal, processing, such as extending the space | interval with the adjacent microradiation source 26, can be performed.

When the error ΔI is within the allowable error (step S18; Yes), the control unit 331 displays to notify the actually measured intensity, the error, and the like (step S20).
The control unit 331 registers the measurement result in the work table as illustrated in FIG. 11B (step S21), and ends the process.

  This completes the process of inserting one minute radiation source 26 into the affected area and measuring its intensity.

Subsequently, the user and the control unit 331 perform the same processing for the next insertion position, in this example, the 007th position reference hole 13a, and execute the insertion and measurement of the minute radiation source 26.
Thereafter, the same operation is repeated until all insertions are completed.
Thus, insertion and measurement are performed in parallel, and insertion and measurement can be performed efficiently.
When all the work is completed, a work table is completed in the storage unit 333 as illustrated in FIG.
If the insertion position is changed / corrected during the work, the input table 335 may be operated to correct the work table as necessary. In addition, the work table can be appropriately displayed on the display unit 336.

Next, an example of a method for setting each measurement parameter in the parameter table 334 stored in the storage unit 333 of the computer 33 will be described. This process may be executed once, for example, at the start of use of the minute radiation source insertion apparatus 1 and thereafter calibrated as appropriate.
First, a calibrated minute radiation source whose intensity is calibrated with high accuracy is prepared.
Next, the sampling period of the radiation sensor 31 is set to a sufficiently short period within a selectable range.

  Next, the computer 33 is operated to execute the operation program stored in the storage unit 333, thereby starting the measurement parameter setting process shown in FIG. When starting the processing, the computer 33 first sets the identification number N of the template 13 to 001 (step S31).

  Next, the user attaches the guide needle 21 to the Nth position reference hole 13 a of the template 13. Subsequently, using a linear actuator or the like, the calibrated minute radiation source is moved by a predetermined distance including at least the measurement area S at an assumed maximum speed (usually about 20 cm / second), and the radiation intensity is detected by the radiation sensor 31. Measure.

  The control unit 331 sequentially takes the measurement values supplied from the radiation sensor 31 and stores them in the storage unit 333 (step S32). The control unit 331 repeats this operation until it is determined that the movement of the calibrated minute radiation source is finished (step S33; Yes). Thereby, the relationship between the time and the measured value as illustrated in FIG. 13 is recorded in the storage unit 333.

  Next, the computer 33 specifies a measurement value acquired during a period in which the calibrated minute radiation source is located in the measurement area S (step S34). The identification method is arbitrary. For example, a maximum value (peak value) of measured values is identified, a series of measured values having a value of 90% or more of the peak value and a continuous sampling period ( For example, SD in FIG. 13 is specified as a value acquired during a period in which the calibrated minute radiation source is located in the measurement area S. Of the specified measurement values, the first and last measurement values may be excluded. Further, the number of measurement values is suppressed so that the sample period × (number of measurement values−1) ≦ LS / V (LS is the length of the measurement area S, V is the moving speed of the calibrated minute radiation source). Also good. In the measurement area S, for example, the position and length can be easily specified by measuring the intensity of radiation with the radiation sensor 31 while moving the calibrated minute radiation source at a low speed (for example, 3 cm / second). . For example, the measured value of the radiation sensor 31 is plotted while moving the calibrated minute radiation source at a low speed (for example, sufficiently slower than the speed of the minute radiation source 26 at the time of insertion, for example, 3 cm / second), and the maximum value of 95 is plotted. A distance at which a measurement value of about% can be obtained can be specified as the distance of the measurement area S.

  Next, the sampling period and the number of samples are obtained so that the time required for the calibrated microradiation source to pass through the measurement area S can be used effectively (step S35). . For example, a combination is selected in which the product of the sampling period and the number of samples that can be selected by the radiation sensor 31 is the maximum value within the time required for the calibrated microradiation source to pass through the measurement area S at the speed V.

Next, an average value AV of the measured values is obtained, and the coefficient k is obtained by dividing the radioactivity (Bq) of the calibrated minute radiation source by this average value AV (step S36).
Next, the obtained sampling period, the number of samples, and the coefficient k are associated with the identification number N and registered in the parameter table 334 in the storage unit 333 (step S37).

  Subsequently, it is determined whether or not the identification number N has reached the final value (step S38). If it has not reached (step S38; No), the identification number N is incremented by 1 (step S39), and the process is repeated.

The user attaches the guide needle 21 to the position reference hole 13a specified by the updated identification number, moves the calibrated minute radiation source, and performs the same processing.
On the other hand, if completed (step S38; Yes), the measurement parameter setting process is terminated.

In order to facilitate understanding, an example in which the identification number N is updated and set in order from 001 has been shown, but the initial value of the identification number N, the update order, and the like are arbitrary.
The process for setting the measurement parameters does not have to be executed for all the insertion positions (position reference holes 13a), but may be executed for a plurality of insertion positions, and others may be set by a complementing method or the like.
Further, the computer 33 used for measurement and the computer used for measurement parameter setting need not be the same.

  As described above, according to the present embodiment, the strength of the microradiation source 26 is efficiently measured because the microradiation source 26 to be inserted automatically measures the strength while the guide needle 21 is moving. It becomes possible. Moreover, even when a mistake occurs, it can be easily detected. Furthermore, although the moving speed of the microradiation source varies greatly depending on the practitioner, appropriate measurement is possible regardless of who is in charge.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation and application are possible. For example, in the above embodiment, when the number of the micro radiation sources 26 inserted into the affected area increases, the radiation from the inserted micro radiation sources 26 cannot be ignored. In such a case, the measured value is as shown in FIG. 14, for example, and a certain amount of radiation is detected even when the minute radiation source 26 is not present in the vicinity. For this reason, with respect to each minute radiation source 26, the measured value (environmental radiation dose) Iini measured at the first step S13 of the radiation source intensity measurement process of FIG. What is necessary is just to subtract from each measured value in step S13, and to use the value after subtraction for the process after above-mentioned step S15.

  In the above-described embodiment, an example in which one type of minute radiation source is inserted into the affected area has been described. However, it is also possible to insert a plurality of types (multiple intensities) of radiation sources. In this case, for example, as shown in FIG. 15, the intensity of the minute radiation source 26 scheduled to be inserted for each reference position hole is registered in the work table, and the difference (error) between the actually measured intensity and the registered scheduled insertion intensity. A warning may be issued when the error exceeds an allowable error.

As an example of the measurement parameter, the sampling period, the number of samples, and the coefficient k are illustrated, but other measurement parameters may be added. Also, for example, the sampling period is set for each position reference hole, the number of samples is common to all position reference holes, or the sampling period is common to all position reference holes, and the sampling period is set for each position reference hole. May be.
In order to facilitate understanding, the intensity of the minute radiation source 26 is obtained by multiplying the measurement value of the radiation sensor 31 by a coefficient k. However, other processing, for example, more complicated calculation is performed, The strength may be obtained.
Although the example using the parameter table 334 has been shown, the measurement parameters may be stored in a form other than the table. Moreover, although the example which uses a work table was shown, whether to use a work table is arbitrary.
In the above embodiment, the template 13 (position reference hole 13a) is used to define the insertion position of the minute radiation source 26. However, other methods can be used as long as the insertion position can be adjusted. .
In addition, the criteria (conditions) to be satisfied in the case of performing warning or notification and the mode of warning and notification are also arbitrary. For example, although the standard is expressed by% of error, for example, the tolerance may be defined by an absolute value of intensity such as ± 3 Bq.

  Moreover, although the example which guide | induces the microradiation source 26 to an affected part using the guide needle 21 was shown, you may guide the microradiation source 26 to an affected part using other arbitrary guides. In this case, when the minute radiation source 26 moves along the guide, its intensity may be measured.

  The numerical values such as the material and size of each part, the flowchart, the types of parameters, etc. are examples and can be changed as appropriate. Further, the measurement method, the measurement parameter setting method, and the like are not limited to the above embodiment, and can be changed as appropriate.

  Furthermore, in the above embodiment, the measurement apparatus and method according to the invention of the present application and the example of application to the insertion device for inserting a microradiation source into the prostate were shown. However, the insertion for inserting the microradiation source into other types of cancer is shown. The present invention can be similarly applied to the apparatus and the insertion method.

  Note that the above-described radiation source intensity measurement processing, measurement parameter setting processing, and the like can be realized by using a normal computer system without using a dedicated system. For example, by installing the program from a medium (flexible disk, CD-ROM, etc.) storing a program for executing the above-described radiation source intensity measurement processing, measurement parameter setting processing, etc. in a general computer, the above-described processing is performed. Can be configured. It is also possible to distribute these programs and recording media storing the programs.

DESCRIPTION OF SYMBOLS 1 Microradiation source insertion apparatus 10 Main body 11 Support part 12 Ultrasonic probe apparatus 12a Ultrasonic probe 13 Template 13a Position reference hole 20 Insertion tool 21 Guide needle 22 Applicator 23 Radiation source cartridge 24 Mounting part 25 Operation part 26 Microradiation source 26a Capsule 26b nuclide 30 measuring unit 31 radiation sensor 32 signal processing circuit 33 computer 321 amplifier 322 A / D (analog-digital) converter 331 control unit 332 input / output I / F (interface)
333 Storage unit 334 Parameter table 335 Input unit 336 Display unit 337 Sound emission unit

Claims (9)

A device for measuring the intensity of a radiation source when inserting the radiation source into an affected area,
A storage unit for storing measurement parameters for each insertion position;
When inserting the radiation source into the affected area, a measurement unit that measures the intensity of the radiation from the radiation source moving along the guide,
The measurement parameter corresponding to the insertion position of the radiation source is identified from the measurement parameters stored in the storage unit, and the radiation source intensity is determined based on the identified measurement parameter and the radiation intensity measured by the measurement unit. A control unit for obtaining
A radiation source intensity measuring apparatus comprising: The measurement parameters include a measurement sampling period, the number of measurement values to be employed, and a coefficient for determining the intensity of the radiation source from the measurement values,
The measurement unit performs measurement at a sampling period specified by the measurement parameter,
The control unit records a series of measurement values acquired by the measurement unit, extracts a number of measurement values specified by the measurement parameter from the recorded measurement values, and extracts the measurement values and measurements To determine the intensity of the radiation source based on the parameters,
The radiation source intensity measuring apparatus according to claim 1. The measurement unit has directivity and has a certain measurement area in which radiation from a radiation source can be appropriately measured,
The control unit extracts a measurement value measured when the radiation source is in the measurement area from a series of stored measurement values.
The radiation source intensity measuring apparatus according to claim 2. The measurement parameter is set to a numerical value based on the maximum movement speed of the radiation source when the radiation source is inserted into the affected part, and the intensity of the radiation source can be obtained even when moving at the maximum movement speed.
The radiation source intensity measuring apparatus according to claim 1, 2, or 3. Provided with a notification means for performing a predetermined notification when the intensity obtained by the control unit and a preset planned intensity satisfy a predetermined criterion;
The radiation source intensity measuring apparatus according to claim 1, wherein the radiation source intensity measuring apparatus is a radiation source intensity measuring apparatus.   The measurement parameter is obtained by moving a calibrated radiation source having a known intensity along the guide for each insertion position, measuring the intensity of radiation from the calibrated radiation source, and measuring the measured radiation intensity and the calibrated The radiation source intensity measuring apparatus according to claim 1, wherein the radiation source intensity measuring apparatus includes one obtained from the intensity of the radiation source.   A radiation source insertion device comprising the radiation source intensity measurement device according to claim 1. A method of measuring the intensity of a radiation source when inserting the radiation source into an affected area,
Obtain measurement parameters for each insertion position,
Measure the intensity of radiation from the moving radiation source toward the affected area at the time of insertion,
Identify the measurement parameter corresponding to the insertion position, and determine the intensity of the radiation source based on the identified measurement parameter and the measured radiation intensity.
A radiation source intensity measuring method characterized by the above. On the computer,
Processing to store measurement parameters for each position where the radiation source is inserted into the affected area;
A process of recording the measurement results of a measuring device that measures the intensity of radiation from a moving radiation source for insertion into the affected area;
A process for determining the measurement parameter based on the insertion position, and determining the intensity of the radiation source based on the specified measurement parameter and the recorded radiation intensity;
A computer program that executes

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