Depth aperture and X-ray system

Abstract

The utility model relates to a depth aperture (1) for delimiting an X-ray beam (11) of a medical X-ray system (16), the depth aperture (1) is provided with an aperture housing (14), the aperture housing (14) is provided with an upper aperture plate (2) for delimiting the X-ray beam (11) close to a focus and a lower aperture plate (4) for delimiting the X-ray beam (11) close to a detector, a light unit for emitting visible light is formed, the light unit being arranged in such a way that the visible light enters the interior of the aperture housing (14) at least partially through a recess in the aperture housing, the recess being sealed substantially impermeable to X-ray radiation by means of a lead glass element (5). The utility model also relates to an X-ray system (16) with the depth aperture.

Description

Technical Field

[0001] The utility model relates to a deep aperture with a lead glass element and an X-ray system. The lead glass element is used for shielding X-ray radiation and simultaneously allows visible light to enter the inner space of an aperture housing. Background Art

[0002] X-ray systems, in particular radiographic systems or fluoroscopic systems, usually include a depth aperture for limiting the X-ray beam. The depth aperture can be arranged in particular directly at the exit window of the X-ray radiator. Therefore, the X-ray beam is emitted through the exit window of the X-ray radiator and directly enters the depth aperture, in particular the interior space of the aperture housing. The divergent X-ray beam can be limited by means of an aperture plate so that the X-ray beam incident on the object under examination is limited to the examination area or the receiving area. In order to simplify or control the setting of the limitation, a light field is used, which shows the extension of the X-ray beam on the surface of the object under examination facing the X-ray radiator. The light field is also limited in the interior space of the aperture housing, at least by the lower aperture plate, in the same way as the X-ray beam. In this way, a substantially consistent extension of the X-ray beam and the light field on the surface of the object under examination can be achieved.

[0003] Until now, the problem has been solved by a lead shield under the light source. Since the light source can be movably designed, the shield has no fixed position, so that the values ​​can fluctuate during the beam leakage test. In addition, the solution space or installation space of the light source is also limited.

[0004] Collimators or depth apertures are subsystems of all types of fluoroscopic devices. Collimators or depth apertures are placed directly below the X-ray tube or X-ray radiator. Its main task is to filter and cut X-rays or X-ray beams. On the one hand, the X-ray radiator emits unwanted (X-ray) radiation, that is, radiation that is not needed for fluoroscopy; on the other hand, when X-rays hit the components of the collimator or depth aperture, scattered radiation occurs. The unwanted X-ray radiation is mostly blocked from emitting from the depth aperture by various "Shieldings" or shielding (Abschirmung) (for example, a plate with lead glued on it). This is an important function of the collimator or depth aperture, because otherwise it may lead to unwanted absorption of X-ray radiation in the case of an operator. In the area of ​​the light source of the collimator or depth aperture, shielding by lead is only feasible under limited conditions. The light source is especially arranged outside the collimator or depth aperture, and the emitted light is injected into the collimator or depth aperture. As a result, problematic gaps may appear in the radiation shielding of the depth aperture.

[0005] Regardless of the grammatical gender of a particular term, persons having male, female, or other gender identities are included. Utility Model Content

[0006] The object of the present invention is to provide a depth aperture and an X-ray system, which can achieve improved shielding of the environment from unwanted X-ray radiation emitted from the depth aperture.

[0007] According to the utility model, the object is achieved by a deep aperture and an X-ray system.

[0008] The utility model relates to a depth aperture for limiting an X-ray beam of a medical X-ray system, wherein the depth aperture has:

[0009] an aperture housing having an upper aperture plate for delimiting the X-ray beam close to the focal point and a lower aperture plate for delimiting the X-ray beam close to the detector,

[0010] - forming a light unit for emitting visible light, wherein the light unit is arranged in such a way that the visible light is incident at least partially through a recess in the aperture housing into the interior of the aperture housing,

[0011] In this case, the recess is sealed by means of a lead glass element in a manner that is substantially impermeable to x-rays.

[0012] The depth aperture is designed to limit the X-ray beam. The depth aperture is used in medical X-ray systems. The medical X-ray system can be, in particular, a radiography system, a fluoroscopy system, a uroscopy system, a mammography system, an angiography system or another fluoroscopy system.

[0013] The depth aperture comprises an aperture housing and a light unit. The aperture housing comprises an upper aperture plate and a lower aperture plate. The upper aperture plate or the lower aperture plate can be arranged in an aperture plane as an aperture pair facing each other in particular. For example, the lower aperture plate and / or the upper aperture plate can each comprise two aperture pairs, in which the fading direction is offset by 90 degrees between the pairs. The two aperture pairs can be arranged one above the other in two parallel aperture planes. The aperture plate comprises a material that is particularly highly absorbent for X-ray radiation, for example, the material can comprise tungsten. In addition, the aperture plate, in particular the lower aperture plate, can also be impermeable to visible light. Thereby, the aperture plate can be used not only to limit the X-ray beam, but also to limit the light field. The upper aperture plate provides a limit for the X-ray beam close to the focus. The lower aperture plate provides a limit for the X-ray beam close to the detector, and in particular additionally provides a limit for the light field.

[0014] The light unit is designed to emit visible light. The light unit is arranged so that the visible light is incident at least partially through the recess in the aperture housing into the interior space of the aperture housing. The recess can be an opening in the aperture housing. The recess or opening can be open or permeable, in particular, with respect to the visible light. The recess serves as an injection window for the visible light into the interior space.

[0015] The recess is sealed substantially impermeable to X-ray radiation by means of a lead glass element. The lead glass element can be designed to be substantially permeable to optical light and substantially impermeable to X-ray radiation. The lead glass element can seal, cover, fill or close the recess. The lead glass element serves the purpose of being able to achieve or improve shielding of the environment from undesired X-ray radiation.

[0016] The gaps of the shielding or the shielding produced by the light source or the light unit can be filled with lead glass. The use of a light source outside the aperture housing requires a recess in the aperture housing through which light can be incident into the interior space. In view of this, the recess can be mainly represented as a recess as a recess formed in the material of the aperture housing that is essentially impermeable to X-ray radiation. Thus, the recess can form an entrance window for visible light, while the recess can simultaneously be an exit window for unwanted X-ray radiation. In order to prevent or reduce the emission of X-ray radiation, the inventors propose to design and construct the recess so that it is essentially impermeable to X-ray radiation with the help of a lead glass element. As a result, light can be irradiated or incident into the collimator or the deep aperture with little efficiency loss, and the emitted extra-acoustic radiation, i.e., unwanted X-ray radiation, can be advantageously reduced to a minimum.

[0017] The lead glass element comprises lead glass as material. The lead glass element comprises in particular a layer of lead glass which is extended in such a way that the recess can be substantially sealed with respect to X-ray radiation. Lead glass or also lead crystal glass is produced from lead oxide in proportions. In the form of pure lead glass, the lead oxide proportion is at least 24%. Other components of the lead glass are, depending on the composition: SiO 2 (55%-67%), Soda Na 2 O (5%-15%), and potassium carbonate K 2 O(5%-15%).

[0018] Gaps in the shield or recesses in the aperture housing are advantageously closed and the emitted X-ray radiation is further reduced. In addition, new possibilities for designing the light module are provided in terms of design.

[0019] According to one aspect of the invention, the lead equivalent of the lead glass element corresponds substantially to the lead equivalent of the wall element of the aperture housing adjoining the recess. The lead equivalent describes the layer thickness required to achieve the same shielding strength or absorption rate for a specific lead thickness relative to X-ray radiation. In the energy range of the X-ray recording, the lead equivalent is calculated with the aid of the following formula:

[0020]

[0021] Here, a, b, c, d are known constants, and ρ is expressed in g / cm 3 is the material density of the unit, ρ 0 1g / cm 3 , U is the X-ray tube voltage in kV, U 0 is 100 kV, x is the lead thickness in mm, and x 0 The lead equivalent of the lead glass element can advantageously be selected to correspond substantially to the lead equivalent of the aperture housing. This allows the emission or penetration to be designed uniformly for the aperture housing. In the case of completely covering the recess, further protective measures can advantageously be omitted.

[0022] According to one aspect of the invention, the lead glass element has a lead equivalent of at least 1 mm lead. Advantageously, a large portion of the undesired X-ray radiation can be absorbed by the lead glass element.

[0023] According to one aspect of the utility model, the lead glass element is round, angular or polygonal. The lead glass element can be shaped in particular to correspond to the cutout. Advantageously, the lead glass element can seal the cutout in a substantially exact fit. Alternatively, the lead glass element can completely cover the cutout, so that the lead glass element has a greater extension than the cutout. Advantageously, the emission of undesired X-ray radiation can be reduced.

[0024] According to one aspect of the utility model, the recess is formed at the side of the aperture housing. The recess can be formed in particular between the aperture plane of the upper aperture plate and the aperture plane of the lower aperture plate in the side wall of the aperture housing. Thereby, the light unit can be arranged outside the aperture housing. Thereby, it can be avoided that the light unit is located in the direct X-ray beam, thereby negatively affecting the uniformity of the X-ray beam and reducing the service life of the light unit. In addition, it can also be avoided that the light source or light unit is in the interior space as an additional scattering source.

[0025] According to one aspect of the utility model, the lead glass element is fixedly connected to the light unit. Advantageously, the lead glass element can be prevented from sliding relative to the light unit. Advantageously, the lead glass element can be connected to the aperture housing together with the light unit.

[0026] According to one aspect of the utility model, the lead glass element is surrounded by a frame element and is screwed to the light unit. The lead glass can be placed in the frame and screwed to the light source or the light unit. Advantageously, a simplified connection to the light unit can be established via the frame element.

[0027] According to one aspect of the utility model, the lead glass element is fixedly connected to the aperture housing. Advantageously, the lead glass element can be prevented from sliding relative to the aperture housing. Advantageously, protection from emitted undesired X-ray radiation can be reliably ensured.

[0028] According to one aspect of the invention, the X-ray beam and the light field incident on the object under examination have a substantially identical extension. The identical extension can be formed mainly in one plane on the surface facing the X-ray radiator. In this way, the limitation of the X-ray beam can be advantageously checked or set by means of the gradual appearance of the light field. Advantageously, incorrect or suboptimal limitations can be avoided for recording.

[0029] According to one aspect of the utility model, a mirror unit is arranged in the aperture housing to deflect the light field from the light unit into the propagation direction of the X-ray beam. Advantageously, the light can be deflected by means of the mirror unit into substantially the same propagation direction along which the X-ray radiation of the X-ray beam also propagates. Advantageously, the light field can display the extension of the X-ray beam on the surface of the object under examination.

[0030] According to one aspect of the utility model, the light unit is movable, which is advantageous in that the light unit can be replaced in a simpler manner, and is advantageous in that the light unit can be adjusted in a simpler manner.

[0031] According to one aspect of the invention, the light unit comprises an LED. Advantageously, an extended service life or an extended maintenance interval can be achieved. Advantageously, the light color can be selected or predetermined.

[0032] According to one aspect of the present invention, the aperture housing has a shielding element at least in a subregion. Advantageously, undesired X-ray radiation from the aperture housing at the exit can be prevented or reduced.

[0033] The utility model also relates to an X-ray system, in particular a medical X-ray system, having a depth aperture according to the utility model. The X-ray system comprises an X-ray radiator and a depth aperture connected to the X-ray radiator. The X-ray beam emitted by the X-ray radiator is incident on the X-ray detector and is attenuated at least partially by the object under examination. The advantages of the depth aperture according to the utility model can be advantageously transferred to the X-ray system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The following is a more detailed description of an embodiment of the present invention based on the accompanying drawings. It is shown here:

[0035] Figure 1 A schematic diagram of an X-ray system according to the present invention is shown. DETAILED DESCRIPTION

[0036] Figure 1 An exemplary embodiment of an X-ray system 16 according to the invention is shown having an X-ray radiator 10 and a depth aperture 1 .

[0037] The depth aperture 1 is used to delimit an X-ray beam 11 of a medical X-ray system 16 and has the following components:

[0038] an aperture housing 14 having an upper aperture plate 2 for delimiting the X-ray beam 11 close to the focal point and a lower aperture plate 4 for delimiting the X-ray beam 11 close to the detector,

[0039] - forming a light unit 13 for emitting visible light, wherein the light unit 13 is arranged such that the visible light is incident at least partially through a recess in the aperture housing 14 into the interior of the aperture housing 14 ,

[0040] The recess is sealed in this case by means of a lead glass element 5 in a manner that is substantially impermeable to x-rays.

[0041] The depth aperture 1 is designed to delimit an X-ray beam 11. The depth aperture 1 is used in a medical X-ray system 16. The medical X-ray system 16 can be, in particular, a radiography system, a fluoroscopy system, a uroscopy system, a mammography system, an angiography system or another fluoroscopic system.

[0042] The depth aperture 1 comprises an aperture housing 14 and a light unit 13. The aperture housing 14 comprises an upper aperture plate 2 and a lower aperture plate 4. The upper aperture plate 2 or the lower aperture plate 4 can be arranged in an aperture plane as an aperture pair facing each other. For example, the lower aperture plate 2 and / or the upper aperture plate 4 can each comprise two aperture pairs, in which the fading direction is offset by 90 degrees between the pairs. The two aperture pairs can be arranged one above the other in two parallel aperture planes. The aperture plates 2, 4 have a material that is particularly highly absorbent for X-ray radiation, for example, the material can include tungsten. In addition, the aperture plates, in particular the lower aperture plate 4, are also impermeable to visible light. Thereby, the aperture plates 2, 4 can be used not only to limit the X-ray beam 11, but also to limit the light field 12. The upper aperture plate 2 provides a limitation of the X-ray beam 11 close to the focus. The lower aperture plate 4 provides for the delimitation of the x-ray beam 11 close to the detector and in particular also for the delimitation of the light field 12 .

[0043] The light unit 13 is configured to emit visible light. The light unit 13 is arranged so that the visible light is incident at least partially through the cutout in the aperture housing 14 into the interior space of the aperture housing 14. The cutout may be an opening in the aperture housing 14. The cutout or opening may be open or permeable, in particular, to the visible light. The cutout serves as an injection window for the visible light into the interior space.

[0044] The recess is sealed substantially impermeable to X-ray radiation by means of a lead glass element 5. The lead glass element 5 can be designed to be substantially permeable to optical light and substantially impermeable to X-ray radiation. The lead glass element 5 can seal, cover, fill or close the recess. The lead glass element 5 serves the purpose of being able to achieve or improve shielding of the environment from undesired X-ray radiation.

[0045] The gaps of the shielding or the shielding produced by the light unit 13 can be filled with lead glass. By using a light source or the light unit 13 outside the aperture housing 14, a recess is required in the aperture housing 14, through which light can be incident into the interior space. In view of this, the recess can be mainly represented as a recess formed in the material of the aperture housing 14 that is essentially impermeable to X-ray radiation. Therefore, the recess can form an entrance window for visible light, while the recess can simultaneously be an exit window for unwanted X-ray radiation. In order to prevent or reduce the emission of X-ray radiation, the inventors propose to design and construct the recess so that it is essentially impermeable to X-ray radiation by means of a lead glass element 5. Therefore, light can be irradiated or injected into the collimator or the depth aperture 1 with little efficiency loss, and the emitted extra-acoustic radiation, that is, unwanted X-ray radiation, can be advantageously reduced to a minimum.

[0046] The lead glass element 5 comprises lead glass as material. The lead glass element 5 comprises in particular a layer of lead glass extending downward, i.e., such that the recess can be substantially sealed with respect to X-ray radiation. Lead glass or also lead crystal glass is produced from lead oxide in proportions. In the form of pure lead glass, the lead oxide proportion is at least 24%. Other components of the lead glass are, depending on the composition: SiO 2 (55%-67%), Soda Na 2 O (5%-15%), and potassium carbonate K 2 O(5%-15%).

[0047] Preferably, the lead equivalent of the lead glass element 5 corresponds substantially to the lead equivalent of the wall elements of the aperture housing 14 adjoining the recess.

[0048] According to one aspect of the invention, the lead glass element has a lead equivalent of at least 1 mm lead. Advantageously, a large portion of the undesired X-ray radiation can be absorbed by the lead glass element.

[0049] The lead glass element 5 can be round, angular or polygonal. The lead glass element 5 can be shaped in particular to correspond to the cutout. The lead glass element 5 can seal the cutout in a substantially exact match. Alternatively, the lead glass element 5 can completely cover the cutout, so that the lead glass element 5 has a greater extension than the cutout.

[0050] The cutout is formed on the side of aperture housing 14. The cutout is formed in particular between the aperture plane of upper aperture plate 2 and the aperture plane of lower aperture plate 4 in the side wall of aperture housing 14. As a result, light unit 13 can be arranged outside aperture housing 14.

[0051] The lead glass element 5 can be fixedly connected to the light unit 13. Preferably, the lead glass element 5 is surrounded by a frame element and is screwed to the light unit 13. The lead glass element 5 can be inserted into a frame and screwed to the light unit 13.

[0052] The lead glass element may be fixedly connected to the aperture housing.

[0053] The X-ray beam 11 and the light field 12 incident on the examination object have a substantially identical extension. The identical extension can be formed mainly in one plane on the surface facing the X-ray radiator 10. In this way, the limitation of the X-ray beam 11 can be advantageously checked or set by means of the gradual appearance of the light field 12.

[0054] A mirror unit 15 is arranged in the aperture housing 14 to deflect the light field 12 from the light source or light unit 13 into the propagation direction of the X-ray beam 11. The light is deflected by means of the mirror unit into substantially the same propagation direction in which the X-rays of the X-ray beam 11 also propagate.

[0055] In one embodiment, the light unit 13 may be movable. The light unit 13 preferably comprises an LED. The aperture housing may preferably have a shielding element at least in a sub-region.

[0056] The depth aperture 1 has a set of upper aperture plates 2 close to the focus, which are mainly used to suppress out-of-focus radiation. At the output end of the depth aperture 1, there is another set of lower aperture plates 4, which keep the width of the half-shadow border (Halbschattensaum) small, and the half-shadow border surrounds the X-ray beam 11 due to the expansion of the focal spot.

[0057] The aperture groups of aperture plates 2 , 4 are coupled to one another so that the field of view can be adjusted manually or motor-driven, for example via a drive device (not shown), such as a stepper motor. After passing through an object (not shown), the X-ray beam 11 strikes the X-ray detector 3 .

[0058] The orientation and size of the effective radiation field are checked by projecting the light field 12 onto a patient (not shown) (= light crosshair). For this purpose, a light unit 13 is located laterally in an aperture housing 14, the light field 12 of which coincides with the radiation field of the X-ray beam 11 via a mirror unit 15 located in the X-ray beam path.

[0059] During the recording of the X-ray image, the depth aperture 1 can be rotated, for example, up to 45° about the central beam axis of the X-ray beam 11 for a more precise fading-in of the X-ray beam 11 adapted to the anatomical conditions. In order to display the X-ray recording in full size on the screen without requiring additional work steps by the user, the image processing system can detect the fading-in edge and the X-ray image can be displayed rotated and enlarged based on the fading-in edge.

[0060] Although the details of the present implementation have been described in detail through the preferred embodiments, the present invention is not limited to the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the protection scope of the present invention.

Claims

1. A depth aperture (1) for limiting an X-ray beam (11) of a medical X-ray system (16), characterized in that: The depth aperture (1) has: an aperture housing (14) having an upper aperture plate (2) for delimiting the X-ray beam (11) close to the focus and a lower aperture plate (4) for delimiting the X-ray beam (11) close to the detector, and - forming a light unit for emitting visible light, wherein the light unit is arranged so that the visible light is incident at least partially through a recess in the aperture housing into the interior of the aperture housing (14), The recess is sealed in a substantially impermeable manner to X-ray radiation by means of a lead glass element (5).

2. The depth aperture according to claim 1, wherein the lead equivalent of the lead glass element substantially corresponds to the lead equivalent of a wall element of the aperture housing adjacent to the recess.

3. A depth stop according to claim 1 or 2, wherein the lead glass element has a lead equivalent of at least 1 mm lead.

4. The depth aperture according to claim 1 or 2, wherein the lead glass element is designed to be circular, angular or polygonal. 5 . The depth aperture according to claim 1 , wherein the recess is formed on a side surface of the aperture housing.

6. The depth aperture according to claim 1 or 2, wherein the lead glass element is fixedly connected to the light unit.

7. The depth aperture according to claim 1 or 2, wherein the lead glass element is surrounded by a frame element and is screwed with the light unit.

8. The depth aperture according to claim 1 or 2, wherein the lead glass element is fixedly connected to the aperture housing.

9. The depth aperture according to claim 1 or 2, wherein the X-ray beam (11) and the light field (12) incident on the examination object have a substantially identical extension.

10. The depth aperture according to claim 1 or 2, wherein a mirror unit (15) is arranged in the aperture housing in order to deflect the light field (12) from the light unit (13) into the propagation direction of the X-ray beam (11).

11. The depth aperture according to claim 1 or 2, wherein the light unit is movable.

12. The depth aperture of claim 1 or 2, wherein the light unit comprises an LED. 13 . The depth stop according to claim 1 , wherein the stop housing has a shielding element at least in a subregion.

14. An X-ray system (16), characterized in that The X-ray system has a depth aperture (1) according to any one of claims 1 to 13.

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