Radiation shields and radiation protection glasses

Abstract

The present invention provides a radiation shield and radiation protective eyewear that can reduce the amount of X-rays absorbed by the lens of the eye of the operator performing the X-ray fluoroscopy examination during the examination process. [Solution] The radiation shield 100 of the present invention is a radiation shield to be attached to eyeglasses, and comprises a flexible sheet 101 containing a material that absorbs radiation, a shape-retaining member 102 that holds the sheet 101 in a predetermined three-dimensional shape, and a fixing means 103 that allows the sheet 101 to be attached and fixed to one temple of the eyeglasses.

Description

Technical Field

[0001] The present invention relates to a radiation protection shield and radiation protection glasses.

Background Art

[0002] It has been reported that radiation-induced cataracts have occurred in operators involved in X-ray fluoroscopy examinations in medical facilities. In particular, during X-ray examinations such as EPCP (endoscopic retrograde cholangiopancreatography), operators wear radiation protection glasses, but it is considered that the X-rays scattered from the examination target are not sufficiently blocked from irradiating the lens of the operator's eyes. In fact, events where scattered X-rays that pass through the head tissues and reach the lens are not completely blocked have been confirmed from the sides and rear of the operator. Since the lens is highly radiation-sensitive, it is considered to be exposed by being irradiated with scattered X-rays. Since April 2021, the revised Ionizing Radiation Injury Prevention Regulations have been implemented, and the equivalent dose limit for the lens of the eye related to occupational exposure has been significantly lowered, and a technology for shielding scattered X-rays traveling towards the lens and reducing the exposure of the lens is required.

[0003] In Patent Document 1, a radiation protection device provided with a lens protection part for the eye is disclosed. However, this lens protection part is considered to be a sheet-like object fixed with a plate-like object or a frame, etc., and is fixed in a flat shape. Therefore, even when this lens protection part covers the surface of the face, it is difficult to adhere to the surface without gaps, and it is considered difficult to block scattered X-rays passing through the gaps.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention has been made in view of the above circumstances, and aims to provide a radiation shield and radiation protective glasses that can reduce the amount of X-rays absorbed by the lens of the eye of the operator performing the X-ray fluoroscopy examination during the examination process. [Means for solving the problem]

[0006] To solve the above problems, the present invention employs the following means.

[0007] (1) A radiation shield according to one aspect of the present invention is a radiation shield to be attached to eyeglasses, comprising a flexible sheet containing a material that absorbs radiation, and a shape-retaining member that holds the sheet in a predetermined three-dimensional shape.

[0008] (2) The radiation shield described in (1) above may further include a housing means configured to house the sheet and be attached to one temple of the eyeglasses.

[0009] (3) In the radiation shield described in (2) above, the shape-retaining member may be attached to at least one of the sheet and the housing means.

[0010] (4) A radiation shield described in any one of (1) to (3) above may further include a fixing means for which the sheet can be attached to and fixed to one of the temples of the eyeglasses.

[0011] (5) In the radiation shield described in any one of (1) to (4) above, it is preferable that when attached to the eyeglasses, the length of one side of the sheet that is closer to the lens of the eyeglasses is 8 cm or more, and the length of the other side of the sheet that is opposite to the first side is 6 cm or more.

[0012] (6) In the radiation shield described in any one of (1) to (5) above, the shape-retaining member may be a wire-shaped member.

[0013] (7) In the radiation shield described in any one of (1) to (6) above, the shape-retaining member may be attached along at least a portion of the outer circumference of the sheet.

[0014] (8) In the radiation shield described in (4) above, the fixing means may be a clip capable of gripping the sheet and the temple of the eyeglasses while the sheet is attached to one temple of the eyeglasses.

[0015] (9) A radiation-protective pair of glasses according to one aspect of the present invention has a radiation-protective shield described in any one of (1) to (8) above attached to one of the temples.

[0016] (10) The radiation protection glasses described in (9) above may be equipped with a balancer attached to the other temple to stabilize the wearing state.

[0017] (11) The radiation protection glasses described in (9) or (10) above may be provided with a band that connects both temples of the glasses and stabilizes the wearing state. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a radiation shield and radiation protective glasses that can reduce the amount of X-rays absorbed by the lens of the eye of the operator performing the X-ray fluoroscopy examination during the examination process. [Brief explanation of the drawing]

[0019] [Figure 1] This is a plan view of a radiation shield according to one embodiment of the present invention. [Figure 2] This is a perspective view of radiation protection glasses, which consist of a radiation protection shield and glasses according to the same embodiment. [Figure 3] This is an illustrative diagram showing the radiation protection glasses of the same embodiment being worn by a surgeon. [Figure 4]It is a diagram showing a state where a sheet is housed in a bag. [Figure 5] (a), (b) It is a diagram schematically showing a state where an operator 12 wearing a radiation protection shield of the same embodiment is performing an X-ray fluoroscopy examination on a patient 13. [Figure 6] It is a plan view showing a modification example of the sheet of the same embodiment. [Figure 7] (a), (b) It is a plan view showing a modification example of the shape retaining member of the same embodiment. [Figure 8] (a), (b) It is a perspective view showing a modification example of the radiation protection goggles of the same embodiment. [Figure 9] (a) to (c) It is a graph comparing the relationship between the orientation of the operator's body and the dose of X-rays at the position of the lens surface while changing the conditions of the goggles. [Figure 10] It is a graph comparing the relationship between the orientation of the operator's body and the dose of X-rays at the position of the lens surface while changing the conditions of the sheet. [Figure 11] (a) to (c) It is a graph comparing the relationship between the orientation of the operator's body and the dose of X-rays at the position of the lens surface while changing the length of one side of the outer periphery of the sheet. [Figure 12] (a), (b) It is a graph comparing the relationship between the orientation of the operator's body and the dose of X-rays at the position of the lens surface while changing the length of the other side of the outer periphery of the sheet.

Embodiments for Carrying out the Invention

[0020] Hereinafter, a radiation protection shield and radiation protection goggles according to an embodiment to which the present invention is applied will be described in detail with reference to the drawings. Note that the drawings used in the following description may show, for the sake of clarity of the features, parts that are characteristic in an enlarged manner, and the dimensional ratios of each component are not necessarily the same as the actual ones. Also, the materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited thereto, and it can be appropriately changed and implemented without changing the gist thereof.

[0021] Figure 1 is a perspective view of a radiation shield 100 according to one embodiment of the present invention. The radiation shield 100 is a radiation shield that is attached to eyeglasses used by a surgeon in an environment where radiation is present. Figure 2 is a perspective view of radiation protective eyeglasses 200, which consist of eyeglasses 10 and a radiation shield 100 attached to one temple 11 of the eyeglasses 10. Figure 3 is an image of the radiation protective eyeglasses 200 being worn by a surgeon 12. The surgeon's head 12A is shown by a dashed line. The radiation shield 100 mainly comprises a sheet 101, a shape-retaining member 102, and a fixing means 103. The radiation shield 100 may further include a housing means configured to house the fixing means 103 and the sheet 101.

[0022] Sheet 101 is made of lead or contains a radiation-absorbing material other than lead at a predetermined density and is flexible. Sheet 101 may be a cloth-like material such as an olefin resin. Examples of radiation-absorbing materials include bismuth oxide, barium sulfate, and tungsten powder. If the density of the contained radiation-absorbing material is the same, a thicker sheet 101 is preferable, and the thickness may be increased by making a single sheet thick or by stacking multiple sheets together. The flexibility of sheet 101 is assumed to be similar to that of a nonwoven fabric used to make a mask, for example. Flexibility can be evaluated, for example, by a pure bending test.

[0023] The sheet 101 is attached to the eyeglasses 10 by covering or contacting one of the temples 11 of the eyeglasses 10 with a part of the sheet 101 (such as an end) and then fixing it using the fixing means 103. When the eyeglasses 10 with the sheet 101 attached are worn by the operator, the area around the operator's eye is covered by the sheet 101. The main surface of the sheet 101 has a shape and size that covers an area at a predetermined distance from the position of the lens of the eye (5.5 cm or more in the lateral direction from the outer circumference of the lens, preferably 7 cm or more, and 6 cm or more in the vertical direction, preferably 8 cm or more). The shape of the main surface of the sheet 101 is not particularly limited and may be rectangular, trapezoidal, polygonal, or even without corners.

[0024] Figures 1-3 illustrate a sheet 101 with a trapezoidal main surface. The sheet 101 is attached to the eyeglasses 10 so that when the operator puts on the eyeglasses 10, the longest side of the outer circumference of the sheet 101 is closest to the operator's eye 12B. In Figure 3, this longest side is the longer side (first side) 101a of the upper or lower base. The first side 101a is the side closer to the eyeglass lens 20 when the sheet 101 is attached to the eyeglasses 10. The other shorter side (second side) 101b of the upper or lower base is relatively farther from the operator's eye. The second side 101b is opposite the first side 101a. The shape of the sheet 101 is designed with the shape of the operator's face in mind, with the first side 101a, which is closer to the cheek, being longer. Of the two sides connecting the first side 101a and the second side 101b, the third side 101c, which is farther from the crane 11, is not parallel to the direction of extension of the crane 11.

[0025] From the viewpoint of covering the area around the lens that requires protection, it is preferable that the length La of the first side 101a be 8 cm or more, so as to be able to cover the entire side of the operator's face. Also from the same viewpoint, it is preferable that the length Lb of the second side 101b be 6 cm or more, and more preferable if it is 8 cm or more. Also from the same viewpoint, it is preferable that the distance D between the first side 101a and the second side 101b be 5.5 cm or more, and more preferable if it is 7 cm or more. Note that if the main surface of the sheet 101 is not rectangular and the outer circumference is curved, the lengths of the first side 101a and the second side 101b should be the length connecting their respective ends.

[0026] The shape-retaining member 102 is attached to at least one of the sheet 101 and the storage means. Figure 1 illustrates the case where the shape-retaining member 102 is attached to the sheet 101. The shape-retaining member 102 attached to the sheet 101 is a member that can deform the sheet 101 into a predetermined three-dimensional shape and maintain the deformed shape. When the shape-retaining member 102 is attached to the storage means, it is a member that can deform the sheet 101 into a predetermined three-dimensional shape together with the storage means and maintain the deformed shape. The predetermined three-dimensional shape is, for example, a shape curved to follow the surface of the surgeon's profile. Examples of materials that make up the shape-retaining member 102 include steel. By using the shape-retaining member 102, the sheet 101 can be deformed to follow the surface shape of the surgeon's profile. By covering the surgeon's profile with the deformed sheet 101, the exposed area of ​​the profile can be reduced, and the shielding effect of radiation (in this case, X-rays) directed towards the lens can be increased.

[0027] The shape-retaining member 102 is preferably attached along at least a portion of the outer circumference of the sheet 101. Since the area of ​​the surgeon's face that is particularly curved is near the cheeks and chin, it is preferable that the shape-retaining member 102 is attached to at least the portion of the sheet 101 that covers the area near the cheeks and chin. In the radiation shield 100 of Figure 1, the shape-retaining member 102 is attached to the sheet 101 near the first side 101a that covers the cheeks and near the third side 101c that covers the chin. This allows the sheet 101 to be three-dimensionally deformed to match the curvature of the cheeks and chin, making it fit snugly against the surgeon's face and blocking radiation directed towards the lens from the side (in this case, the left) and rear of the surgeon.

[0028] The shape-retaining member 102 is not particularly limited, but a wire-like member (such as a string-like member extending in one direction) as shown in Figures 1 and 2 is preferable because it can be easily deformed. Figures 1 and 2 illustrate a case where the shape-retaining member (wire-like member) 102 is attached to the vicinity of the first side 101a and the vicinity of the third side 101c of the sheet 101. In this case, the portion 102A attached to the vicinity of the first side 101a and the portion 102B attached to the vicinity of the third side 101c of the shape-retaining member 102 are separate entities, and they may overlap or be integrated.

[0029] The fixing means 103 is a means that enables the sheet 101 to be attached to and fixed to one temple 11 of the eyeglasses 10. Figures 1 and 2 illustrate the case in which a clip 103A is used as the fixing means 103. In this case, the sheet 101 is attached to one temple 11 of the eyeglasses 10 with a portion (end, etc.) covering it or in contact with it, and both the sheet 101 and the temple 11 of the eyeglasses are fixed by being gripped by the clip 103A. Here, the case in which one clip 103A is used in the center of the sheet 101 is illustrated, but it may also be used at the end of the sheet 101 or multiple clips 103A may be used as long as it can be fixed stably.

[0030] Furthermore, the fixing means 103 may combine the functions of fixing and maintaining the shape of the sheet 101. For example, if the gripping part is a clip with a long gripping portion, it can not only fix the sheet 101 but also contribute to the deformation and shape maintenance of the sheet 101 while gripping the temples 11 of the eyeglasses and the sheet 101. When using such a fixing means, the adhesion of the sheet 101 to the operator's face can be improved compared to when only a wire-like member is used as the shape-retaining member 102. When using such a fixing means, the attachment of other shape-retaining members is not essential.

[0031] The sheet 101 may be fixed to the handle 11 by providing a through hole 101e that penetrates the inside of the sheet 101 along the fourth side 101d, at the end of the sheet 101 facing the third side 101c. The sheet 101 can be fixed by passing the handle 11 through this through hole 101e. Alternatively, the fixing may be done by using adhesive means such as adhesive, tape, or fasteners to bond the end on the fourth side 101d to the handle 11.

[0032] Figure 4 shows the state in which the sheet 101 is stored in a predetermined bag 104 when a bag is selected as an example of a storage means. The sheet 101 may be attached to one temple 11 of the eyeglasses 10 in this state. When the sheet 101 is stored in the bag 104, the end of the bag 104 may be placed over or in contact with one temple 11 of the eyeglasses 10 using the fixing means 103, rather than the end of the sheet 101. In this case as well, the fixing means 103 may be a clip 103A as described above, or a through hole may be provided in the end of the bag 104 and used, or an adhesive means may be used.

[0033] The bag 104 shall have the same flexibility as the sheet 101. Preferably, the volume of the bag 104 is large enough to accommodate the entire sheet 101 without bending it, and not to shift position due to the operator's movements. When the sheet 101 is attached directly to the eyeglasses 10, the edges of the attached sheet 101 cannot be used for radiation shielding. In contrast, when the bag 104 containing the sheet 101 is attached to the eyeglasses 10 in the state shown in Figure 4, the bag 104 takes on the role of attachment to the eyeglasses 10, so the entire sheet 101 can be used for radiation shielding.

[0034] Figures 5(a) and (b) schematically show a state in which an operator 12 is performing an X-ray fluoroscopy on a patient (subject to examination) 13 lying on a bed 14, wearing radiation-protective goggles 200 with a radiation shield 100 attached. X-rays (indicated by arrows) are irradiated onto the patient 13 from an X-ray source 15 located above. The operator 12 mainly stands to the side of the patient 13 and works while mainly looking at a monitor 16 that displays information obtained from the X-rays. Some of the X-rays irradiated onto the patient 13 are scattered and indirectly irradiate the operator 12 as well. The scattered X-rays mainly irradiate the operator 12 from the diagonally rear side, from the operator 12's perspective as they look towards the monitor 16. The orientation of the operator's body (facing forward) can be expressed as a rotation angle ±θ from the direction facing the patient phantom.

[0035] Simply wearing glasses is not sufficient to block scattered X-rays emitted from the rear at an angle. As a result, scattered X-rays can reach the lens of the operator's eye, making the lens susceptible to radiation exposure. In contrast, when wearing radiation-protective glasses 200 with a radiation shield 100 attached, the operator's profile is completely covered, effectively blocking scattered X-rays emitted from the rear at an angle, and significantly reducing the probability of the lens being exposed to radiation.

[0036] Figure 6 is a plan view showing sheet 101A, a modified version of sheet 101. Sheet 101A has a pentagonal shape, with the first side 101a protruding away from the second side 101b. The tip of the protruding portion may be curved rather than pointed. The presence of such a protruding portion makes it easier to make sheet 101A fit more closely to the operator's face, and extends the area that can be covered to below the operator's eyes, thereby increasing the shielding rate of X-rays.

[0037] Figures 7(a) and 7(b) are plan views showing modified examples of shape-retaining members 102 attached to the sheet 101. From the viewpoint of increasing the degree of adhesion of the sheet 101 to the surface of the operator's face, the shape-retaining member 102 may use three or more wires. For example, as shown in Figure 7(a), in addition to being attached near the second side 101b and near the third side 101c, the wire 102 may be attached along a line passing between the second side and the third side. Also from the same viewpoint, the shape-retaining member 102 may be a plate-shaped member. For example, as shown in Figure 7(b), it may have a shape similar to the sheet 101 or a different shape.

[0038] Figures 8(a) and 8(b) are perspective views showing modified versions 200A and 200B of the radiation protection glasses 200. In Figure 8(a), the radiation protection glasses 200A are equipped with a balancer 18 on the other temple 17 to which the radiation shield 100 is not attached. In Figure 8(b), the radiation protection glasses 200B are equipped with a band 19 that connects both temples 11 and 17 of the glasses 10. Both radiation protection glasses 200A and 200B can be stabilized when worn by the operator 12 while performing work.

[0039] As described above, the radiation shield 100 of this embodiment has the function of changing and holding a sheet 101 containing a radiation-absorbing material into a predetermined three-dimensional shape. By attaching this radiation shield 100 to the eyeglasses of the operator performing the X-ray fluoroscopy examination and shaping it to conform to the surface of the operator's face, the surface of the operator's face can be covered without gaps, and X-rays directed towards the lens of the eye can be shielded. Therefore, with the radiation shield 100 of this embodiment, the amount of X-rays absorbed by the lens of the operator's eye during the examination process can be reduced, and the probability of the lens being exposed to radiation can be greatly reduced. [Examples]

[0040] The effects of the present invention will be made clearer by the following examples. However, the present invention is not limited to the following examples and can be implemented with appropriate modifications without altering its essence.

[0041] (Example 1) A radiation shield according to the above embodiment was fabricated. The number of sheets was set to 1. For the shape-retaining member, a steel wire with a thickness of approximately 0.4 mm was used and attached along the outer circumference of the sheet as shown in Figure 1. As a means of fixing, a single clip was used to grip the temple of the eyeglasses and the end of the radiation shield placed over the temple, as shown in Figures 1 and 2. The sheet was specified as follows. Length of the first side of the sheet: 8cm, Length of the second side of the sheet: 6cm, Sheet thickness: 0.105 cm, Radiation-absorbing material for the sheet: Bismuth oxide, Density of radiation-absorbing material within the sheet: 2.20 g / cm³ 3 , Lead equivalent: 0.039mmPb.

[0042] Using phantoms of the operator and the patient, the situation in which the operator performs an X-ray fluoroscopy examination was recreated, as shown in Figure 5, with the operator wearing glasses equipped with this radiation shield (radiation protective goggles). The operator phantom's body orientation (facing forward) was rotated at angles of 15°, 30°, 45°, 60°, and 75° from the direction facing the patient phantom. The operator phantom's height was set to three different values: 150cm, 165cm, and 180cm.

[0043] A dosimeter was attached to the position corresponding to the lens of the operator phantom's eye, and the dose of scattered X-rays reaching this position was measured while the patient phantom was irradiated with X-rays to generate scattered X-rays. X-ray irradiation was performed using an X-ray fluoroscopy device under the following conditions. X-ray tube voltage: 73kV, X-ray tube current: 26.9mA X-ray viewing time: 10 minutes, Pulse rate: 15fps Additional filter: 0.2mm Cu, Irradiation field of view: 29.8cm x 29.8cm.

[0044] (Comparative Example 1) The procedure simulated a situation where a surgeon phantom performs an X-ray fluoroscopy examination without wearing glasses. The conditions were the same as in Example 1, except that the surgeon phantom was not wearing glasses, and the dose of scattered X-rays reaching the position of the surgeon phantom's lens was measured.

[0045] (Comparative Example 2) The procedure simulated a situation where an operator phantom wore glasses without radiation shielding while performing an X-ray fluoroscopy examination. The conditions were the same as in Example 1, except that the glasses did not have radiation shielding, and the amount of scattered X-rays reaching the position of the operator phantom's lens was measured.

[0046] Figures 9(a) to (c) are graphs comparing the relationship between the orientation of the operator phantom body obtained in Example 1, Comparative Examples 1 and 2, and the measured dose, when the operator phantom's height was 150 cm, 165 cm, and 180 cm, respectively. The horizontal axis of the graph shows the rotation angle (°) of the operator phantom, and the vertical axis shows the air kerma (mGy).

[0047] In operator phantoms of all heights, the measured dose was lower when wearing glasses with a radiation shield (Example 1) compared to when not wearing glasses (Comparative Example 1) or when wearing glasses without a radiation shield (Comparative Example 2). These results show that by using the radiation shield of the present invention, the amount of X-rays absorbed by the lens of the operator's eye during the examination process can be reduced, thereby reducing the operator's exposure to radiation. In particular, since the measured dose was lower in Example 1 than in Comparative Example 2, it can be seen that in Example 1, scattered X-rays incident from the side and obliquely behind, which are a drawback of glasses, are shielded by the radiation shield.

[0048] Regarding radiation protection shields, the reduction rate of the measured dose when wearing glasses with shields attached (Example 1) compared to when wearing glasses without shields attached (Comparative Example 2) was calculated using the following formula (1). The calculation results are shown in Table 1.

[0049]

number

[0050] [Table 1]

[0051] As shown in Table 1, the reduction rate of the measured dose improves as the operator's rotation angle increases, demonstrating a more pronounced effect of the radiation shield of the present invention. This is because, as the rotation angle increases, the proportion of scattered X-rays that can be blocked by the radiation shield increases compared to the scattered X-rays directed toward the lens.

[0052] (Examples 2-5) Except for using 2 to 5 sheets to constitute the radiation shield, dose measurements were performed in the same manner as in Example 1. The operator phantom was set to 165 cm.

[0053] Figure 9 is a graph comparing the relationship between the orientation of the operator phantom body obtained in Examples 2-5 and the measured dose. The horizontal and vertical axes of the graph are the same as in Figure 9.

[0054] Regarding the sheets that make up the radiation shield, using two or more sheets stacked together significantly reduces the measured dose compared to using only one sheet. Furthermore, there is a tendency for the measured dose to decrease as the number of sheets increases. It is thought that increasing the number of sheets in the radiation shield allows for the inclusion of more radiation-absorbing material, resulting in a higher lead equivalent and thus a higher shielding efficiency.

[0055] For cases where 1 to 5 sheets were attached to the radiation shield (Examples 1 to 5), the lead equivalent was shown, and the reduction rate of the measured dose was calculated using the above formula (1). The calculation results are shown in Table 2.

[0056] [Table 2]

[0057] The more sheets are stacked to increase the lead equivalent, the lower the measured dose becomes. In particular, when three or more sheets are stacked, i.e., when the lead equivalent of the sheets is 0.117 or higher, the reduction rate exceeds 80%. These results confirm the shielding effect of attaching radiation shielding to eyeglasses against X-rays.

[0058] (Examples 6-9) Except for setting the length of the first side of the sheets constituting the radiation shield to 6 cm, 7 cm, 9 cm, and 10 cm, dose measurements were performed in the same manner as in Example 1.

[0059] Figures 11(a) to (c) are graphs comparing the relationship between the orientation of the operator phantom body and the measured dose obtained in Examples 1, 6-9, and Comparative Example 2, when the operator phantom's height was 150cm, 165cm, and 180cm, respectively. The horizontal and vertical axes of the graphs are the same as in Figure 9.

[0060] In operator phantoms of all heights, the measured dose was reduced when the sheet was attached (Examples 1, 6-9) compared to when the sheet was not attached (Comparative Example 2). The reduction rate of the measured dose increased as the length of the first side of the sheet increased. It is thought that as the length of the first side of the sheet increases, the coverage area of ​​the lens expands to the underside of the lens, and the shielding effect against X-rays from below increases.

[0061] For cases where the length of the first side of the sheet attached to the radiation shield was 6 to 10 cm (Examples 1, 6 to 9), the reduction rate of the measured dose was calculated using the above formula (1). The calculation results for cases where the height of the operator phantom was 150 cm, 165 cm, and 180 cm are shown in Tables 3 to 5, respectively.

[0062] [Table 3]

[0063] [Table 4]

[0064] [Table 5]

[0065] In all height cases, the longer the first side of the sheet, the greater the reduction in the measured dose. In particular, when the length of the first side is 8 cm or more, there are angles where the reduction is more than 80%. The measured dose also depends on the distance from the patient phantom, which is the X-ray scattering source, to the lens of the operator's eye. The longer the distance, the lower the dose reaching the lens. This distance increases with the operator's height, so the reduction rate is larger for taller operators.

[0066] (Examples 10, 11) Except for setting the length of the second side of the sheet constituting the radiation shield to 5 cm and 7 cm, dose measurements were performed in the same manner as in Example 1.

[0067] Figures 12(a) and (b) are graphs comparing the relationship between the orientation of the operator phantom's body and the measured dose obtained in Examples 1, 10, 11, and Comparative Example 2, when the operator phantom's height is 165 cm and 180 cm, respectively. The horizontal and vertical axes of the graphs are the same as in Figure 9.

[0068] In operator phantoms of all heights, the measured dose was reduced when the sheet was attached (Examples 1, 10, and 11) compared to when the sheet was not attached (Comparative Example 2). The reduction rate of the measured dose increased as the second side of the sheet was lengthened. It is thought that as the second side of the sheet is lengthened, the coverage area of ​​the lens extends to the rear and diagonally downward side of the lens, and the shielding effect against X-rays from the rear and diagonally downward side is enhanced.

[0069] For cases where the length of the second side of the sheet attached to the radiation shield was 5 to 7 cm (Examples 1, 10, and 11), the reduction rate of the measured dose was calculated using the above formula (1). The calculation results for cases where the height of the operator phantom was 165 cm and 180 cm are shown in Tables 6 and 7, respectively.

[0070] [Table 6]

[0071] [Table 7]

[0072] In all height cases, the longer the second side of the sheet, the greater the reduction in the measured dose, and the reduction is particularly large when the length of the second side is 6 cm or more. The reason why the reduction rate is larger for taller individuals is, as mentioned above, because the distance from the patient phantom to the lens of the operator's eye increases. [Explanation of Symbols]

[0073] 100... Radiation protection shield 101...seat 101a... First side of the sheet 101b...Second side of the sheet 101c... Third side of the sheet 101d... Fourth side of the sheet 101e... Through hole in sheet 102...Shape-retaining member 103...Fixing means 103A... Clip 104 bags 10...glasses 11... One of the vines 12. Practitioner 12A... The surgeon's head 12B... The Surgeon's Eye 13...patient 14... Bed 15...X-ray source 16...Monitor 17. The other crane 18. Balancer 19.. Band 20... lenses D... Distance between the first and second sides La... First side length Lb...Length of the second side

Claims

1. A radiation shield that attaches to eyeglasses, A flexible sheet containing radiation-absorbing material, A radiation shield comprising a shape-retaining member for holding the sheet in a predetermined three-dimensional shape.

2. The radiation shield according to claim 1, further comprising a housing means configured to house the sheet and be attached to one temple of the eyeglasses.

3. The radiation shield according to claim 2, characterized in that the shape-retaining member is attached to at least one of the sheet and the housing means.

4. The radiation shield according to claim 1 or 2, further comprising a fixing means for attaching and securing the sheet to one temple of the eyeglasses.

5. When attached to the aforementioned eyeglasses, the length of one side of the sheet that is closer to the lenses of the eyeglasses is 8 cm or more. The radiation shield according to claim 1 or 2, characterized in that the length of the other side of the sheet opposite to the one side is 6 cm or more.

6. The radiation shield according to claim 1 or 2, characterized in that the shape-retaining member is a wire-shaped member.

7. The radiation shield according to claim 1 or 2, characterized in that the shape-retaining member is attached along at least a portion of the outer circumference of the sheet.

8. The radiation shield according to claim 4, characterized in that the fixing means is a clip capable of gripping the sheet and the temple of the eyeglasses while the sheet is attached to one temple of the eyeglasses.

9. Radiation protection glasses characterized in that the radiation protection shield described in claim 1 or 2 is attached to one of the temples.

10. The radiation protection glasses according to claim 9, further comprising a balancer attached to the other temple to stabilize the wearing state.

11. The radiation protection glasses according to claim 9, further comprising a band that connects both temples of the glasses and stabilizes the wearing state.

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