JP5072662B2 - Absorbed dose management device - Google Patents

Description

  The present invention relates to an absorbed dose management apparatus that manages the absorbed dose of medical staff engaged in the vicinity of radiation equipment.

  In recent years, there has been an increase in relatively minimally invasive interventional procedures for performing procedures under fluoroscopy at the request of patients. In interventional surgery, the individual patient dose does not change much, but the medical staff dose increases.

  Conventionally, exposure management of medical staff depends on periodic measurement using a radiation measuring instrument such as a film badge, and the obligation to display the exposure area defined by the IEC (International Electrotechnical Commission).

  However, in reality, radiation measuring instruments such as film badges cannot detect the dose in real time, and regular measurements such as once a month reduce the staff's awareness of exposure, and the dose is unknown and unknown. It has become a lot.

Moreover, although the display of the exposure area | region prescribed | regulated by IEC is described in the instruction manual, in many cases, it cannot be said that it is actually utilized for dose management.
JP 2004-0665815 A

  An object of the present invention is to provide an absorbed dose management apparatus for precisely managing the absorbed dose of medical staff around the radiation equipment.

  In one aspect of the present invention, the absorbed dose management apparatus includes a storage unit that stores data relating to a dose spatial distribution around a radiation device, a position detection unit that detects a position of a medical staff around the radiation device, and the dose. An absorbed dose estimating unit for estimating a cumulative absorbed dose of the medical staff based on a spatial distribution and the position of the medical staff.

  ADVANTAGE OF THE INVENTION According to this invention, the absorbed dose of a medical staff can be managed accurately.

  First, an outline of absorbed dose management by the absorbed dose management apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 1 shows the flow of an absorbed dose management operation in this embodiment. As shown in FIG. 1, based on the dose distribution representing the spatial distribution of the dose related to the periphery of the radiation equipment such as the X-ray diagnostic apparatus, and the position of the medical staff existing around the radiation equipment, Calculate (estimate) the absorbed dose (cumulative absorbed dose) that medical staff receives cumulatively, and notify when the cumulative absorbed dose reaches a predetermined amount. Specifically, the absorbed dose corresponding to the position absorbed by the medical staff is sequentially identified from the dose distribution, and the cumulative absorbed dose is calculated by integrating the exposure dose over time. In particular, the cumulative absorbed dose is calculated not only for the current radiological examination but also for the absorbed dose in the past radiological examination.

  FIG. 2 shows a configuration example of the absorbed dose management apparatus according to the embodiment. This absorbed dose management apparatus has the control part 1 as a control center. The absorbed dose management apparatus is connected to an external X-ray diagnostic apparatus or a radiation information system (RIS) via the interface unit 5. Information about X-ray irradiation conditions and information about X-ray generation / stop are supplied from an X-ray diagnostic apparatus and a radiation information system. Information related to X-ray irradiation conditions includes the angle of the C-arm of the X-ray diagnostic apparatus, SID (distance between the X-ray source and detector surface), tube voltage, tube current, X-ray irradiation time, additional filter Multiple items related to dose distribution such as type and collimator type are included. According to these X-ray irradiation conditions, as illustrated in FIG. 3, the spatial distribution of dose (dose distribution) around the X-ray source is determined as a standard. The standard dose distribution database system 3 stores data regarding a plurality of standard dose distributions. A plurality of standard dose distributions respectively correspond to a plurality of X-ray irradiation conditions having at least one item of different numerical values or types. The standard dose distribution database system 3 is under the management of the database management unit 2.

  The absorbed dose management apparatus includes the control unit 1, interface unit 5, standard dose distribution database system 3, input operation unit 4 such as a mouse or keyboard, standard dose distribution customization unit 6, standard dose distribution correction unit 7, dose sensor. 8, a cumulative absorbed dose calculation unit 9, a staff position detection unit 10, a cumulative absorbed dose management unit 11, a display unit 12, and a warning generation unit 13.

  As shown in FIG. 4A, the cumulative absorbed dose calculation unit 9 uses the standard dose distribution read from the standard dose distribution database system 3 using the X-ray irradiation conditions supplied from the X-ray diagnostic apparatus and the radiation information system as search keys, and the staff. The cumulative absorbed dose is estimated for each medical staff from the position.

  The method for estimating the accumulated absorbed dose can be modified as shown in FIGS. 4B to 4E. In order to calculate the cumulative absorbed dose more accurately, a standard dose distribution customization unit 6 may be provided as shown in FIG. 4B. As shown in FIG. 5, the standard dose distribution customizing unit 6 sets the standard dose distribution corresponding to the X-ray irradiation conditions supplied from the X-ray diagnostic apparatus and the radiation information system in advance by installing the X-ray diagnostic apparatus with the dose sensor 8. Customized for each hospital according to the dose measured at multiple locations in the examination room.

  Further, in order to accurately calculate the cumulative absorbed dose, a standard dose distribution correction unit 7 may be provided as shown in FIG. 4C. The dose distribution correction unit 7 corrects the standard dose distribution or the customized standard dose distribution according to the situation at the time of the examination. The situation at the time of the examination includes the dose at a specific location measured in real time by the dose sensor 8 at the time of the examination, peripheral devices such as monitors arranged in the examination room and their positions, the number and positions of medical staff, the patient's body shape (weight, Height, body thickness) and at least one of its positions.

  Regarding the correction of the standard dose distribution with the dose at a specific location measured in real time, specifically, as shown in FIG. 6, the real-time dose is applied to a bed, ceiling, room wall, monitor, drip stand, guard plate, etc. The sensor 8 is mounted, and the dose distribution is corrected in real time based on the output information. The real-time dose sensor 8 is assumed to be a Geiger counter, a combination of a pocket dosimeter and a CCD camera, or an X-ray sensor installed in protective clothing or protective glasses.

  In addition, as shown in FIG. 4D, the standard dose distribution correction unit 7 may correct the standard dose distribution in consideration of peripheral devices and staff positions. Regarding the correction of the standard dose distribution according to peripheral devices, specifically, protective devices (X-ray shielding plates), monitors (displays), protective scarves, respirometers, electrocardiographs, etc. are assumed as peripheral devices. The For example, the shape of these peripheral devices and the X-ray absorption rate are stored in advance in a model calculation formula. As shown in FIG. 7, the position of the protective plate can be grasped in real time by a position sensor described later.

  Regarding the correction of the standard dose distribution with the staff position information, specifically, as shown in FIG. 8, when a plurality of staff exists in the examination room, the staff shadowed from the X-ray source has a dose of Correct small. The correction amount is calculated using a human body model (X-ray absorption rate) of the front staff. The position of the staff can be grasped in real time by a position sensor described later.

  Further, as shown in FIG. 4E, the standard dose distribution correction unit 7 may correct the standard dose distribution in consideration of the patient shape and position. Regarding the correction of the standard dose distribution with the patient body shape (elongation, weight, body thickness) and position, specifically, as shown in FIG. 9, information from the X-ray device (tube voltage, tube current, X-ray pulse) A width supporter position, an X-ray filter, etc.) and patient information (gender, weight, height, age) are input, a device model and a human body model are generated, and a radiation trajectory is calculated. From this result, the exposure dose in each part of the patient's body and the air dose around the inspection device are calculated.

  As shown in FIG. 10, the staff position detection unit 10 detects a staff position with a CCD camera. A CCD camera is provided in the examination room. These cameras monitor staff positions and movement trajectories in real time. The staff movement trajectory distinguishes a plurality of staff members. For personal discrimination, for example, a method of discriminating by a face pattern by image processing is employed.

  As shown in FIG. 11, the staff position information matches the dose distribution with the origins. The movement trajectory of the staff is typically detected from the image of the CCD camera. As a means for specifying the position of the staff, an infrared sensor, a magnetic sensor, an ultrasonic sensor, an optical sensor, or a floor sensor for detecting the weight of the staff may be adopted instead of the CCD camera. good. Individual identification uses a technique such as changing the type of sensor or the frequency of a signal.

  Staff critical organs should be individually managed for exposure. For example, since the lens of the eye has a lower tolerance limit than the skin, it is preferable to distinguish and display the organs. In order to individually calculate and manage the exposure dose of important organs, the height and the position of each organ are stored in advance. Instead of storing each organ position, a sensor may be attached to each organ. The presence / absence of a staff protector can also be used as a parameter for dose calculation. Whether the protector is present or not is determined by either pressing the button according to the presence or absence of the protector by the staff, or determining whether the protector is used or not by attaching a sensor to the protector.

  As shown in FIG. 12, the procedure for notifying the medical staff and the radiation manager of the cumulative absorbed dose is as follows: 1) Display the dose at which the staff is standing 2) Cumulative absorbed dose from the start of surgery 3) Shows the amount of tolerance up to the preset tolerance limit 4) Turns on the warning lamp when the accumulated absorbed dose exceeds the predetermined threshold value 5) When the operation is over, It is assumed that the absorbed dose is displayed.

  The absorbed dose is notified in real time on the screen shown in FIG. Staff warnings should be transparent to the patient. The warning to the staff may be displayed or may be caused by vibration.

  The accumulated absorbed dose is notified on the screen shown in FIG. 14 for each part, for example. The accumulated absorbed dose from the start of the operation may be displayed, or the accumulated absorbed dose on that day may be displayed. Of course, the accumulated absorbed dose for one month may be displayed as the accumulated absorbed dose.

  As shown in FIG. 15, the remaining possible amount up to the allowable limit value may be displayed together with the cumulative absorbed dose. As shown in FIG. 16, the degree of arrival of the cumulative absorbed dose up to the allowable limit value is expressed in%. You may make it display with. The remaining possible amount is displayed as absorbed dose or working time. As the remaining work time, it displays how many more work can be done. The remainder of the working time is calculated back from the average dose per hour from the start of the procedure. Information from cumulative dosimeters such as film badges can be used as the past cumulative absorbed dose. The acceptable level is almost determined by the past dose, gender, age, etc.

  In the above description, the example of the intervention has been described, but the present invention can be applied as it is to X-ray diagnosis, CT, and radiotherapy. The dose distribution in the examination room is acquired in advance, the position of the staff in the examination room is detected, and the dose is notified to the staff working in the exposed area from the spatial positional relationship between the two.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

Schematic which shows the flow of operation | movement in embodiment of this invention. The figure which shows the structure of the absorbed dose management apparatus which concerns on embodiment of this invention. The figure which shows the standard dose distribution memorize | stored in the database system of FIG. Explanatory drawing regarding the process sequence of estimation of the accumulated absorbed dose based on the standard dose distribution from the database system of FIG. Explanatory drawing regarding the other process sequence of estimation of the accumulated absorbed dose based on the standard dose distribution from the database system of FIG. Explanatory drawing regarding the other process sequence of estimation of the accumulated absorbed dose based on the standard dose distribution from the database system of FIG. Explanatory drawing regarding the other process sequence of estimation of the accumulated absorbed dose based on the standard dose distribution from the database system of FIG. Explanatory drawing regarding the other process sequence of estimation of the accumulated absorbed dose based on the standard dose distribution from the database system of FIG. Explanatory drawing regarding the correction of the standard dose distribution by the customization part of the customization part of FIG. 2, and the correction part. The figure which shows installation of the dosimeter of FIG. The figure which shows the dose distribution corrected by the guard plate factor by the correction part of FIG. The figure which shows the dose distribution corrected by the staff factor by the correction part of FIG. FIG. 3 is a supplementary diagram regarding correction of dose distribution according to patient thickness and the like by the correction unit of FIG. The figure which shows the structural example of the staff position detection part of FIG. The figure which shows matching with the coordinate system of the dose distribution by the cumulative absorbed dose calculation part of FIG. 2, and the coordinate system of a staff position detection. FIG. 3 is an operation explanatory diagram regarding the notation, recording, and warning of the cumulative absorbed dose calculated by the cumulative absorbed dose calculation unit of FIG. 2. The figure which shows the example of a display of the absorbed dose by the cumulative absorbed dose management part of FIG. The figure which shows the other example of a display of the absorbed dose by the cumulative absorbed dose management part of FIG. The figure which shows the other example of a display of the absorbed dose by the cumulative absorbed dose management part of FIG. The figure which shows the other example of a display of the absorbed dose by the cumulative absorbed dose management part of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Control part, 2 ... Database management part, 3 ... Standard dose distribution database system, 4 ... Input operation part, 5 ... Interface part, 6 ... Standard dose distribution customization part, 7 ... Dose distribution correction part, 8 ... Dose sensor, DESCRIPTION OF SYMBOLS 9 ... Cumulative absorbed dose calculation part, 10 ... Staff position detection part, 11 ... Cumulative absorbed dose management part, 12 ... Display part, 13 ... Warning generation part

Claims (11)

A storage unit for storing data relating to a dose spatial distribution around the radiation device;
A position detection unit for detecting the position of medical staff around the radiation device;
An absorbed dose management apparatus comprising: an absorbed dose estimation unit that estimates a cumulative absorbed dose of the medical staff based on the dose spatial distribution and the position of the medical staff.   The absorbed dose management apparatus according to claim 1, further comprising a display unit that displays the accumulated absorbed dose.   The absorbed dose management apparatus according to claim 1, further comprising a warning generation unit that generates a warning when the accumulated absorbed dose exceeds a predetermined threshold.   The absorbed dose management apparatus according to claim 1, wherein the absorbed dose estimation unit estimates a cumulative absorbed dose after the start of an operation using the radiation device.   5. The absorbed dose estimation unit estimates at least one of a cumulative absorbed dose on the day of the surgical procedure and a cumulative absorbed dose during a recent predetermined number of days together with the cumulative absorbed dose after the start of the surgical procedure. The absorbed dose management device described.   6. The absorbed dose according to claim 5, wherein at least one of the cumulative absorbed dose on the day of the surgical procedure and the cumulative absorbed dose during the recent predetermined days is displayed simultaneously with the cumulative absorbed dose after the start of the previous surgical procedure. Management device.   The absorbed dose management apparatus according to claim 1, wherein the absorbed dose estimation unit estimates the cumulative absorbed dose for each of a lens, a neck, a chest, an abdomen, and a foot.   The absorbed dose management apparatus according to claim 1, wherein the absorbed dose estimation unit estimates the cumulative absorbed dose based on the presence or absence of X-ray protective clothing.   9. The absorbed dose management apparatus according to claim 8, wherein the accumulated absorbed dose for each of the presence or absence of the X-ray protective clothing is displayed simultaneously.   3. The absorbed dose management apparatus according to claim 2, wherein an allowable absorbed dose is displayed together with the cumulative absorbed dose.   The absorbed dose management apparatus according to claim 2, wherein a ratio of the cumulative absorbed dose to an allowable absorbed dose is displayed together with the cumulative absorbed dose.

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