RU36956U1 - DEVICE FOR DETERMINING AN EFFECTIVE DOSE OF PATIENT IRRADIATION IN X-RAY DIAGNOSTIC RESEARCH - Google Patents

Description

DEVICE FOR DETERMINING AN EFFECTIVE DOSE OF IRRADIATION OF THE NATIONAL AT X-RAY DIAGNOSTIC

RESEARCH

The utility model relates to x-ray technology and can be used to determine the effective dose in x-ray studies.

A device is known for determining the product of a dose per area using an ionization chamber at the outlet of an x-ray emitter. The determination of the effective dose to the patient is made on the basis of the measured product of the dose per area, taking into account the parameters of the study: the focal length, the organ under study and the projection, the patient’s age and anode voltage.

The disadvantage of this measurement method is the inability to determine the dose from the values of the amount of electricity during exposure and the inability to take into account the change in the effective dose due to changes in the anode voltage.

A device is known for determining the effective radiation dose of a patient during an X-ray diagnostic study, comprising a data processing unit including blocks for setting an effective radiation dose from an organ under study, its projection and patient age, the input terminal of the data processing unit is connected to the output of the X-ray apparatus, and the output is connected to the display through a multiplier, to the second input of which a signal is proportional to the amount of electricity flowing through the x-ray tube. (see RF patent No. 2019919 publ. 15.09. 94g. bull. No. 17)

As an input quantity in such a device, the amount of electricity flowing through the x-ray tube for the study is used, and all the set parameters are calibrated in the values of the specific effective dose, referred to 1 mA. Such a device is not able to determine the dose from the measured value of the radiation output, does not take into account its changes during operation and when the anode voltage changes.

The technical task of the utility model is to increase the accuracy of registration of the effective dose received by the patient during an X-ray diagnostic study.

The technical problem is achieved by the fact that in the device for determining the effective dose of a patient during x-ray examination containing a processing unit

data, including blocks for setting the effective dose of radiation from the studied organ, its projection and patient age, the input terminal of the data processing unit connected to the output of the X-ray apparatus and the output connected to the display through a multiplier, to the second input of which a signal is proportional to the amount of electricity flowing through the x-ray tube, in the data processing unit, the unit for setting the effective radiation dose from the anode voltage and the correction unit for changing the focal length, the processing unit The data cage contains an additional five input terminals, one of which contains a signal from an ionization chamber measuring the product of the dose by the area, and each of the other four contains the signal for setting the effective radiation dose from the organ under study and its projection, patient age, anode voltage, and correction from changes in focal length, the second output of the data processing unit is connected to the display through a second multiplier, to the second input of which a signal is proportional to the value of the product of the radiation output (rad cheniya) to the square region) eniya.

The proposed device is free from the above disadvantages. It is a specialized specialized calculator, where the specified parameters are the physical and technical conditions of the study: the working field.

the anode voltage, the focal length, the organ under study, the projection of the survey, the age of the patient, and measured - the amount of electricity through the tube or the product of the dose per area, depending on the x-ray equipment used. The dependence of the patient dose on these parameters is established according to known tables and entered into the data processing unit.

The proposed device is illustrated in the drawing, where in Fig.1 shows a General diagram of the device, in Fig. 2 - shows the experimental dependence of the specific effective dose.

The device includes a data processing unit 1, in which the units for setting the effective radiation dose from the study parameters are combined: the studied organ and its projection 2, patient age 3, anode voltage 4 and the correction unit for changing the focal length 5. Data processing unit 1 has an input terminal 6 connected to the output of the x-ray apparatus (not shown in the drawing), an input terminal 7, to which a signal is supplied from an ionization chamber measuring the product of the dose by the area, as well as input terminals 8, 9, 10 and 11, connected directly to the units for setting the effective radiation dose from the study parameters: the organ under study and its projection 2, patient age 3, anode voltage 4 and the correction unit from changing the focal length 5, respectively. On the

each input terminal 8, 9, 10 and 11 is given a signal to set the effective dose of radiation from the given parameters, respectively, specifically for each patient.

The data processing unit 1 is equipped with two outputs 12 and 13. The output 12 of the data processing unit 1 is connected to the display 14 through a multiplier 15, to the second input of which 16 a signal is supplied from an x-ray tube (not shown in the drawing). The output 13 of the data processing unit 1 is also connected to the display 14 through a second) PM scissor 17, to the second input of which 18 a signal is proportional to the value of the product of radiation

exit (radiation) to the irradiation area.

The device operates as follows.

A signal is applied to the measuring input 6 or 7 of the data processing unit 1 depending on the composition of the X-ray apparatus (input 6) or on the ionization chamber measuring the product of the dose by the area (input 7). Each input 6 or 7 of the device operates autonomously. At each of the inputs 8, 9, 10, and 11 of data processing unit 1, a signal is set for setting the effective radiation dose from the parameter under study: the organ under study and its projection (block 2), patient age (block 3), anode voltage (block 4), and correction from changing the focal length (block 5). The signals from inputs 8.9, 10.11 and inputs 6 or 7 are received in the processing unit

1, where the value of the specific effective dose per 1 mAS (output 12) or the value of the specific effective dose per 1 mSv / cm (output 13) is calculated. From output 12, the signal goes to the multiplier 15, where the specific dose is multiplied by 1 mA, flowing through the x-ray tube during the exposure time at input 16. From output 13, the signal goes to the second multiplier 17, where the multiplication by the radiation output in mGy cm is performed, obtained from input 18. With the help of one of the multipliers 15 or 17, the value of the effective equivalent dose per patient is formed, which is fixed on the display 14. In FIG. Figure 2 shows the experimental dependences of the specific effective dose per 1 mAc and 1 cGy.cm for two age groups (one year and 15 years) in the study of the stomach, obtained on phantom measurements using tissue-equivalent phantom. The specific doses are more effective than E (μSv / mAs), B (μSv / sbc cm) in the study of the stomach for patients of different ages from the voltage on the tube. Similar dependences exist for the values of the effective radiation dose, depending on the other studied organs and age groups.

Thus, thanks to the proposed device, the accuracy of registration of the effective dose received by the patient during x-ray examination is increased.

The device can be implemented both using an electronic calculator, and on a standard computer, which implements all the controls and measuring inputs.

Claims (1)

A device for determining an effective radiation dose for a patient during an X-ray diagnostic study, comprising a data processing unit including blocks for setting an effective radiation dose from the organ under study, its projection and patient age, the input terminal of the data processing unit is connected to the output of the X-ray apparatus, and the output is connected to the display via a multiplier , to the second input of which a signal is proportional to the amount of electricity flowing through the x-ray tube, characterized in that it contains ok data processing, a unit for setting the effective radiation dose from the anode voltage and a correction unit for changing the focal length have been introduced, and the data processing unit has an additional five input terminals, one of which receives a signal from an ionization chamber that measures the product of the dose by the area, and each of the other four signal setting the effective dose of radiation from the studied organ and its projection, patient age, anode voltage and correction from changes in focal length, while the second block output and the data processing is connected to the display through a second multiplier, to the second input of which a signal is proportional to the value of the product of the radiation output (radiation) by the irradiation area.