Magnetic resonance imaging device with lighting device

Abstract

The invention relates to a magnetic resonance system comprising a scanning unit, a patient accommodation area at least partially enclosed by the scanning unit, and a lighting device with at least one lighting element, wherein the lighting device is designed to illuminate the patient accommodation area, wherein the lighting device comprises two compensation elements for compensating for voltages induced by a high-frequency field of the scanning unit.

Description

Technical Field

[0001] The invention relates to a magnetic resonance system comprising a scanning unit, a patient receiving area at least partially enclosed by the scanning unit, and a lighting device with at least one lighting element, wherein the lighting device is designed to illuminate the patient receiving area. Background Art

[0002] For magnetic resonance examinations, a patient, particularly the area of ​​the patient to be examined, is located in the patient accommodation area of ​​the magnetic resonance system. To ensure that the patient remains comfortably within the patient accommodation area during the magnetic resonance examination, it is proposed to illuminate the patient accommodation area. This is accomplished by means of a lighting device of the magnetic resonance system, which is arranged within the patient accommodation area. However, due to this arrangement, the lighting device, particularly its lighting elements, is also exposed to the high-frequency field (HF field) of the high-frequency antenna of the magnetic resonance system. This, however, can lead to interference during the lighting operation of the lighting device.

[0003] To counteract and / or compensate for these interferences, it has been previously proposed to connect a capacitor in parallel with each lighting element, such as an LED, located in the patient accommodation area. The capacitance of the capacitor short-circuits the RF field, thereby reducing the RF voltage induced in the circuit of the lighting device. This also reduces the RF voltage applied to the lighting element. However, this design of the lighting device has the following disadvantage: the lighting element and capacitor are arranged as shown below, and the RF field acts through this surface. This results in interference voltages being induced by the RF field via the small surface between the lighting element and the capacitor. Summary of the Invention

[0004] The present invention is based in particular on the object of enabling non-interfering illumination of the patient accommodation area during a magnetic resonance examination. This object is achieved by the features of the present invention. Advantageous embodiments are described below.

[0005] The present invention is based on a magnetic resonance system having a scanning unit, a patient receiving area at least partially enclosed by the scanning unit, and a lighting device with at least one lighting element, wherein the lighting device is designed to illuminate the patient receiving area.

[0006] According to the invention, the lighting device has two compensation elements for at least partially compensating for the voltage induced by the high-frequency field of the scanning unit.

[0007] The scanning unit preferably includes a detector unit, in particular a magnet unit, for detecting medical and / or diagnostic image data. Preferably, the scanning unit, in particular the magnet unit, includes a base magnet, a gradient coil unit, and a high-frequency antenna unit. A strong, homogeneous, and constant basic magnetic field is generated by means of the base magnet. A high-frequency magnetic resonance sequence is radiated into the patient accommodation area by means of the high-frequency antenna unit, thereby generating a high-frequency field (HF field) in the area enclosed by the high-frequency antenna unit.

[0008] The patient accommodation area is preferably at least partially surrounded by the scanning unit. The patient accommodation area can, for example, be cylindrically configured and / or cylindrically surrounded by the scanning unit. The scanning unit can include a housing that surrounds the patient accommodation area. This housing can also be integrally and / or integrally configured with the high-frequency antenna unit of the scanning unit. The field of view (FOV) and / or isocenter of the magnetic resonance system are preferably provided within the patient accommodation area. The FOV preferably includes a detection area of ​​the magnetic resonance system within which ideal conditions exist for detecting medical image data within the patient accommodation area. The isocenter of the magnetic resonance system preferably includes an area and / or point within the magnetic resonance system with optimal and / or most ideal conditions for detecting medical image data. The isocenter includes, for example, the most homogeneous basic magnetic field area within the magnetic resonance system.

[0009] For an MRI examination, a patient, particularly the area of ​​the patient to be examined, is placed and / or positioned in a patient accommodation area. To this end, the patient is first positioned on an examination couch. The couch, along with the patient positioned on the couch, is then moved into the patient accommodation area until the area of ​​the patient to be examined is within the FOV and / or isocenter of the MRI apparatus, particularly a scanning unit. The couch has a support area with a support surface for positioning and / or supporting the patient.

[0010] The lighting device is configured to illuminate the patient accommodation area. To this end, the lighting device comprises at least one lighting unit with lighting elements. The at least one lighting element can preferably include an LED (light-emitting diode). The lighting device, in particular the lighting unit, comprises two compensation elements, wherein the two compensation elements are configured and / or designed to at least partially compensate for and / or reduce voltages induced by a magnetic field, in particular an HF field, of the scanning unit, in particular interference voltages induced in the at least one lighting element. Preferably, the two compensation elements are arranged and / or connected in parallel with the at least one lighting element.

[0011] In this case, the lighting device can comprise a single lighting unit or also two or more lighting units. If the lighting device has more than one lighting unit, the individual lighting units of the lighting device are preferably designed to be structurally identical.

[0012] Interference voltages applied to at least one lighting element can, for example, cause the at least one lighting element to flicker and / or pulsate. This, in turn, can cause the patient to feel uneasy during an MRI examination. The two compensation elements can advantageously reduce and / or suppress the induced interference voltages on the at least one lighting element. This allows for interference-free illumination of the patient accommodation area during an MRI examination. Consequently, the lighting device according to the present invention can also provide comfort to the patient during an MRI examination.

[0013] In an advantageous refinement of the magnetic resonance system, at least one of the two compensation elements includes a capacitor. Preferably, each of the two compensation elements includes a capacitor. Due to the electrical loop, a surface is developed between the lighting element and the compensation element, in particular the capacitor. The RF field passes through this developed surface and induces and / or causes undesirable voltages, in particular interference voltages. The two capacitors can advantageously reduce these undesirable voltages, in particular interference voltages, directly at the lighting element. This allows for interference-free operation of the at least one lighting element in the RF field of the magnetic resonance system. In particular, this allows for interference-free operation of the at least one lighting element while the RF field is incident on the patient accommodation area.

[0014] A voltage is induced in the HF field by means of a compensation element, particularly a compensation element formed by a capacitor. Providing two compensation elements, particularly two capacitors, can advantageously compensate for this induced voltage. Advantageously, providing two compensation elements, particularly two capacitors, can advantageously compensate for adverse effects, particularly voltages induced in the HF field and applied to at least one lighting element, caused by providing compensation elements, particularly capacitors, in the lighting circuit to reduce the voltage induced by the HF field. In particular, the voltage coupled into the lighting device can be reduced to up to one-fifth of its original value. Particularly advantageously, the voltage coupled into the lighting device can be reduced to up to one-eighth of its original value. Particularly advantageously, the voltage coupled into the lighting device can be reduced to up to one-tenth of its original value.

[0015] In an advantageous refinement of the magnetic resonance system, it can be provided that at least one capacitor has a capacitance of a maximum of 100 nF. Particularly advantageously, at least one capacitor has a capacitance of a maximum of 50 nF. Particularly advantageously, at least one capacitor has a capacitance of a maximum of 20 nF. Particularly advantageously, at least one capacitor has a capacitance of 10 nF. This allows the resonant frequency of an undesired oscillating circuit generated and / or formed in the RF field of the scanning unit by means of the capacitor to be sufficiently distant from the magnetic resonance frequency. This advantageously reduces and / or prevents the initiation of the loop current of the oscillating circuit. Consequently, overheating and / or disruptive heating of components of the oscillating circuit and / or the lighting system can also be advantageously reduced and / or prevented. Furthermore, local B1 inhomogeneities in the B1 field can also be reduced and / or prevented. However, it is also generally provided that capacitors less than 10 nF, for example, 1 nF, can be used.

[0016] In an advantageous refinement of a magnetic resonance system, a first of the two compensating elements is arranged upstream of at least one lighting element, and a second of the two compensating elements is arranged downstream of the at least one lighting element. In particular, the at least one lighting element is arranged and / or connected in parallel with the first and second compensating elements within the lighting circuit of the lighting system. As a result, each compensating element, for example, via a capacitor, induces a voltage in the RF field, where the two voltages can advantageously at least partially compensate and / or cancel each other. This can, in particular, reduce interference voltages applied to the at least one lighting element, thereby enabling trouble-free operation of the at least one lighting element during an MRI examination. This also reduces maintenance costs. The lighting system can be less dependent on the precise properties of the lighting elements, in particular LEDs, such as charge carrier lifetime. This also reduces the risk of having to select and use new components for the lighting unit.

[0017] In one advantageous refinement of the magnetic resonance system, the two compensation elements can be designed to be identical in structure. In particular, the two compensation elements each include a capacitor. Furthermore, the two capacitors can have the same capacitance. This makes it particularly advantageous to compensate for and / or offset interference voltages induced in the HF field by the capacitors and applied to the at least one lighting element.

[0018] Conversely, if field inhomogeneities are present or known, the two capacitors can also have different capacitances in order to compensate for voltages induced in the HF field at the lighting element. This makes it particularly advantageous to compensate and / or eliminate induced voltages applied to at least one lighting element.

[0019] In an advantageous development of the magnetic resonance system, it can be provided that at least one lighting element comprises an LED. This makes it possible to provide a particularly cost-effective lighting element for illuminating the patient accommodation area.

[0020] In one advantageous refinement of the magnetic resonance system, the lighting device can be at least partially disposed within the patient accommodation area and / or an opening of the scanning unit. The opening of the scanning unit preferably includes the patient accommodation area. In particular, the lighting device can also be at least partially disposed on a housing of the scanning unit that surrounds the patient accommodation area. This allows for direct illumination of the patient accommodation area, thereby eliminating the need for light transmission elements that transmit light from outside the patient accommodation area into the patient accommodation area for illumination purposes. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Further advantages, features and details of the invention result from the exemplary embodiments described below and with reference to the drawings.

[0022] The accompanying drawings show:

[0023] Figure 1 A schematic diagram showing a magnetic resonance device with an illumination device according to the present invention,

[0024] Figure 2 A schematic diagram showing a lighting device integrated on a circuit board, and

[0025] Figure 3 A lighting device with induced interference voltage is shown. DETAILED DESCRIPTION

[0026] exist Figure 1 , a magnetic resonance system 10 is schematically shown. The magnetic resonance system 10 includes a scanning unit 11 formed by a magnet unit. The magnetic resonance system 10 also has a patient accommodation area 12 for accommodating a patient 13. In the present embodiment, the patient accommodation area 12 is cylindrical and is surrounded in a cylindrical manner in the circumferential direction by the scanning unit 11, in particular by the magnet unit. In principle, however, different configurations of the patient accommodation area 12 are conceivable. The patient 13 can be pushed and / or moved into the patient accommodation area 12 by means of a patient support device 14 of the magnetic resonance system 10. For this purpose, the patient support device 14 has an examination bed 15 that is movably configured within the patient accommodation area 12. In particular, the examination bed 15 is supported so as to be movably in the longitudinal direction of the patient accommodation area 12 and / or in the z-direction.

[0027] The scanning unit 11, in particular the magnet unit, includes a superconducting base magnet 16 for generating a strong, homogeneous, and in particular constant basic magnetic field 17. Furthermore, the scanning unit 11, in particular the magnet unit, has a gradient coil unit 18 for generating magnetic field gradients, which are used for spatial encoding during imaging. The gradient coil unit 18 is controlled by a gradient control unit 19 of the magnetic resonance system 10. The scanning unit 11, in particular the magnet unit, also includes a high-frequency antenna unit 20 for exciting the polarities that occur in the basic magnetic field 17 generated by the base magnet 16. The high-frequency antenna unit 20 is controlled by a high-frequency antenna control unit 21 of the magnetic resonance system 10 and radiates high-frequency magnetic resonance sequences into the patient accommodation area 12 of the magnetic resonance system 10. This generates a high-frequency field (HF field) in the patient accommodation area.

[0028] The magnetic resonance system 10 has a system control unit 22 for controlling the base magnet 16, the gradient control unit 19, and the high-frequency antenna control unit 21. The system control unit 22 centrally controls the magnetic resonance system, for example, executing a predetermined imaging gradient echo sequence. Furthermore, the system control unit 22 includes an evaluation unit (not shown in detail) for evaluating the medical image data acquired during the magnetic resonance examination.

[0029] The magnetic resonance apparatus 10 further comprises a user interface 23 connected to the system control unit 22. Control information, such as imaging parameters, and reconstructed magnetic resonance images can be displayed to a medical operator on a display unit 24 of the user interface 23, such as at least one monitor. The user interface 23 further comprises an input unit 25, by means of which the medical operator can input information and / or parameters during the measurement process.

[0030] In order to illuminate the patient accommodation area 12, the magnetic resonance device 10 has an illumination device 30. The illumination device 30 has at least one illumination unit 31. Figure 1 , a lighting device 30 having a single lighting unit 31 is shown. However, the lighting device 30 is not limited to a configuration having a single lighting unit 31, and the lighting device 30 can also have two or more lighting units 31, for example, which are arranged at different positions within the patient accommodation area 12.

[0031] An illumination device 30 and / or an illumination unit 31 is disposed within the opening 26 of the scanning unit 11. The opening 26 of the scanning unit 11 encompasses the patient accommodation area 12. Furthermore, the opening 26 of the scanning unit 11 also encompasses a housing 27 that surrounds the patient accommodation area 12. The illumination device 30, in particular the illumination unit 31, is disposed on the housing 27 that surrounds the opening 26. The illumination device 30, in particular the illumination unit 31, can be disposed on the housing 27, for example, in a recess in the housing 27. Preferably, the illumination device 30, in particular the illumination unit 31, is disposed on the housing 27 such that the light and / or light emitted by the illumination device 30, in particular the illumination unit 31, directly enters the patient accommodation area 12. Alternatively or additionally, the illumination device 30, in particular the illumination unit 31, can be disposed on the side of the housing 27 that faces the patient accommodation area 12, such that the illumination device 30, in particular the illumination unit 31, is disposed within the patient accommodation area 12.

[0032] exist Figure 2 and Figure 3 Detailed description of the lighting device 30, in particular the lighting unit 31. The lighting unit 31 is arranged on a circuit board, as shown in FIG. Figure 2 As shown in FIG. 3 , the lighting unit 31 has a lighting element 32 . In the present embodiment, the lighting element 32 is formed by an LED. Furthermore, the lighting unit 31 has at least two compensation elements 33 .

[0033] The two compensation elements 33 are designed and / or constructed to compensate for voltages induced in the lighting device 30, in particular the lighting unit 31, by the magnetic field, in particular the HF field, of the scanning unit 11. The two compensation elements 33 are particularly designed and / or constructed to compensate for interference voltages induced at the lighting elements 32, in particular the LEDs, by the magnetic field, in particular the HF field, of the scanning unit 11.

[0034] The two compensation elements 33 each include a capacitor 34. Each of the two capacitors 34 has a capacitance of at most 100 nF. Particularly advantageously, at least one of the two capacitors 34 or both capacitors 34 have a capacitance of at most 50 nF. Particularly advantageously, at least one of the two capacitors 34 or both capacitors 34 have a capacitance of at most 20 nF. Particularly advantageously, at least one of the two capacitors 34 or both capacitors 34 have a capacitance of 10 nF. In principle, the capacitance of at least one of the two capacitors 34 or both capacitors 34 can be less than 10 nF. For example, a capacitance of at least one of the two capacitors 34 or both capacitors 34 of 1 nF or 2 nF is also conceivable.

[0035] Since the HF field is formed as a homogeneous magnetic field, the two capacitors 34 are designed to be identical in structure. In particular, the two capacitors 34 have the same capacitance. If the magnetic field, in particular the HF field, is formed inhomogeneously, the two capacitors 34 may also be formed with different capacitances.

[0036] The lighting unit 31 is configured such that a lighting element 32, in particular an LED, and two capacitors 34 are connected in parallel within the lighting unit 31, in particular in a lighting circuit 35. The first of the two capacitors 34 is arranged so as to be connected upstream of the lighting element 32, in particular an LED. Furthermore, the second of the two capacitors 34 is arranged so as to be connected downstream of the lighting element 32, in particular an LED. Figure 2 and Figure 3 ).

[0037] By using the compensation element 33 , in particular the capacitor 34 , in the lighting device 30 , in particular the lighting unit 31 , the voltage coupled into the lighting unit 31 can be advantageously reduced and / or compensated.

[0038] Furthermore, by arranging the two capacitors 34 symmetrically relative to the lighting element 32, in particular the LED, within the lighting resonant circuit 35, voltages are induced in each case due to the magnetic field, in particular the HF field, which cancel and / or compensate each other ( Figure 3 ).

[0039] Furthermore, the use of capacitor 34 having such a high capacitance prevents the occurrence of oscillations in the resonant circuit loop current, which is formed and / or generated by means of capacitor 34 in the RF field of scanning unit 11. This results in a sufficiently large distance from the magnetic resonance frequency, so that overheating and / or disruptive heating of components of the resonant circuit and / or lighting device 30 is also reduced and / or prevented.

[0040] The magnetic resonance system 10 shown can of course include further components that are typically present in a magnetic resonance system 10. The general mode of operation of the magnetic resonance system 10 is otherwise known to a person skilled in the art, so that further components do not need to be described in detail.

[0041] Although the details of the present invention have been illustrated and described in detail through preferred embodiments, the present invention is not limited by the disclosed examples and other variations can be derived therefrom by those skilled in the art without departing from the scope of protection of the present invention.

Claims

1. A magnetic resonance apparatus comprising: a scanning unit, a patient accommodation area at least partially enclosed by the scanning unit, and an illumination device configured to illuminate the patient accommodation area. It is characterized by: The lighting device comprises a lighting element, a first capacitor and a second capacitor, wherein the first capacitor and the second capacitor are symmetrically arranged relative to the lighting element (32), and The first capacitor and the second capacitor are symmetrically arranged relative to the lighting element (32), so that voltages induced in the lighting device due to the high-frequency field generated by the scanning unit cancel each other.

2. The magnetic resonance apparatus according to claim 1, It is characterized by: The first capacitor and the second capacitor each have a capacitance of a maximum of 100 nF.

3. The magnetic resonance apparatus according to claim 1, It is characterized by: The first capacitor is arranged in such a way as to be connected upstream of the lighting element, and the second capacitor is arranged in such a way as to be connected downstream of the lighting element.

4. The magnetic resonance apparatus according to claim 1, It is characterized by: The first capacitor and the second capacitor are designed to be structurally identical.

5. The magnetic resonance apparatus according to claim 1, It is characterized by: The lighting element has an LED.

6. The magnetic resonance apparatus according to claim 1, It is characterized by: The lighting device is at least partially arranged in the patient receiving area and / or in an opening of the scanning unit.

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