CN216569931U - Local coil and magnetic resonance system - Google Patents

Abstract

The utility model relates to a local coil for receiving radio-frequency signals in the frequency and power range of a magnetic resonance apparatus, the local coil comprising: the housing has a transparent housing part which is connected to a section of the antenna and is designed to provide an unobstructed line-of-sight connection along a first straight line between the examined body region of the patient and the opening of the magnetic resonance device. The utility model also relates to a magnetic resonance system comprising a local coil, wherein the local coil is electrically connected to a magnetic resonance device via an electrical connection, wherein the electrical connection is designed to establish a signal connection between the local coil and the magnetic resonance device.

Description

Local coil and magnetic resonance system

Technical Field

The utility model relates to a local coil for receiving radio-frequency signals in the frequency and power range of a magnetic resonance device, comprising an antenna, electronics and a housing which surrounds the electronics and the antenna on the outer circumference, wherein the housing has a transparent housing part which is connected to a section of the antenna and is designed to provide an unobstructed line-of-sight connection along a first straight line between an examined body region of a patient and an opening of the magnetic resonance device.

Background

A magnetic resonance tomography apparatus is an imaging device which, for the purpose of imaging an examination subject, orients the nuclear spins of the examination subject by means of a strong external magnetic field and is excited by an alternating magnetic field to precess around the orientation. The precession of the spins, or the return from the excited state to a state with lower energy, in turn generates an alternating magnetic field in response, also referred to as a magnetic resonance signal, which is received via an antenna.

By means of the gradient magnetic fields, a position coding is applied to the signals, which can then be used to correlate the received signals with the volume elements. The received signals are then evaluated and a three-dimensional imaging representation of the object under examination is provided.

To excite the precession of the spins, an alternating magnetic field with a frequency corresponding to the larmor frequency at the corresponding static magnetic field strength and a very high field strength or power are required. In order to improve the signal-to-noise ratio of the magnetic resonance signals received by the antenna, so-called local coils are often used, which are arranged directly at the patient. Local coils usually have an antenna in which an electric current is induced by means of an alternating magnetic field. The current can be amplified by means of a preamplifier and finally transmitted as a signal to the receiving electronics by wire.

The antennas of the local coils can have an electrical potential during the magnetic resonance examination in order to be usually embedded in thermally and/or electrically insulating structures. Such an insulation structure is associated with narrowly designed space requirements on the compactly arranged partial coil. Since local coils usually have multiple antennas for improving the signal-to-noise ratio and for using acceleration techniques (SENSE, GRAPPA), the possibilities for providing a line-of-sight and ventilation opening for the patient can be very limited. This applies in particular to local coils for head applications (head coils) in which it is of high significance to ensure a sufficient field of view and to deliver sufficient breathing air.

A limited line of sight may cause a negative patient experience and lead to interruptions of the magnetic resonance examination, especially for claustrophobic patients. Furthermore, modern magnetic resonance systems make more use of camera systems and optical sensors, which track the motion of the patient during the magnetic resonance examination. The movement of the patient can be, for example, a breathing movement, a swallowing movement or any movement of the limbs. These movements can lead to image artifacts, for example diffuse image noise or ghosting, which can be corrected from the optical data by means of a correction method. In this method, an unobstructed line-of-sight connection to the patient or the body region under examination is imperatively required. Current local coils typically obstruct an unobstructed line of sight to the patient thereby making the use of camera-based correction methods difficult.

Disclosure of Invention

The present invention is therefore based on the object of providing a local coil which improves the line of sight to the patient and increases the comfort of the patient.

The object is achieved by a local coil and a magnetic resonance system.

The local coil for receiving radio frequency signals in the frequency and power range of a magnetic resonance apparatus according to the utility model comprises: an antenna; an electronic component electrically connected to the antenna; and a housing shaped to fit a body region of a patient and surrounding the electronic components and the antenna on an outer circumference.

The antenna can be a coupling element between electromagnetic waves or alternating magnetic fields which are guided in the conductor and which are not guided in the conductor, i.e. which are located in free space. The antenna is preferably designed to receive electromagnetic waves in the range of magnetic resonance frequencies of different magnetic resonance-active nuclei. Electromagnetic waves having a frequency between 1MHz and 500MHz, preferably between 10MHz and 300MHz, are for example considered as radio frequency signals. The magnetic resonance signals of the nuclei to be examined can have, for example, a small power of a few microwatts to several milliwatts.

The antenna can have an electrically conductive metal wire in which an electric current is induced by an alternating magnetic field. It is likewise conceivable for the antenna to be embodied as a printed conductor on a printed circuit board. The antenna is preferably made of copper. In addition, however, other electrically conductive metals, such as gold or aluminum, and combinations thereof, such as silver-plated or gold-plated signal conductors composed of copper, are also conceivable. In addition to metals, it is likewise conceivable to use polymeric conductors, for example polythiophenes or polyanilines, and/or metal oxides, for example ITO (indium tin oxide), FTO (fluorine-doped tin oxide) or AZO (aluminum-doped zinc oxide).

The antenna can be a component of an antenna arrangement with a plurality of antennas and electronic components and/or electronic devices. The antennas of such an antenna arrangement can be present, for example, as an array or matrix of antennas. The antenna preferably has a loop-shaped section which receives a radio-frequency signal of the alternating magnetic field. The loop is for example an approximately annular section of the antenna. The loop may also have another shape. For example, oval shapes or polygonal shapes are conceivable. It is particularly conceivable for the loops to have the shape of lemniscate or to be obtainable from the mentioned shapes by twisting, folding, bending and/or twisting. The antennas are arranged in a matrix or array, for example adjacent side by side or partially overlapping. The matrix may have a regular or irregular arrangement of antennas.

An electronic assembly may include a combination of one or more electronic devices such as, for example, a combination of transistors, resistors, capacitors, diodes, printed wiring, and the like. The electronic component may in particular have a protection circuit which is suitable for protecting the antenna or the antenna arrangement against overload. To avoid magnetic attraction, standing waves, heating and similar undesired effects, the electronic component may have a high share of non-magnetic material and a corresponding sheath current barrier and/or a balun (balun). Furthermore, the electronic component can have a shielding made of an electrically conductive material, which shields the electronic component with respect to the magnetic resonance device. The electrically conductive material can be, for example, gold, silver, aluminum or a base body of any material plated with the aid of said material. Preferably, the electronic circuit has a printed circuit board (printed circuit board) or similar carrier structure which is adapted to receive the electronic components in a predetermined position relative to each other.

The antenna arrangement furthermore has a connection for establishing an electrical connection to the magnetic resonance device. The connection end can comprise an electrical contact which is designed to transmit an electrical signal of the antenna device. The connection of the antenna arrangement is preferably connected to an electrical connection line, which provides a signal connection to the magnetic resonance device.

The housing of the local coil is shaped to the body region of the patient. This can mean that the housing is shaped according to the body region of diagnostic importance or the adjacent region of the diagnostically important volume in the body of the patient. Preferably, the housing can be positioned at the body region in such a way that the antenna and/or the arrangement of the antenna has a distance as small as possible from the diagnostically important body region or the diagnostically important volume in the body of the patient in the application-compliant position of the local coil at the patient. The body region can be, for example, the head, arms, legs, shoulders, torso, hips, or other body parts of the patient. The housing of the local coil preferably has a substantially cylindrical shape or a planar, square shape. However, any variation of these shapes and other shapes that are contoured to the body region of the patient are contemplated.

The antenna and the electronic components are surrounded by a housing on the outer circumference. This can mean that the antenna and the electronic component are embedded in and/or encapsulated by the material of the housing. The housing can have a thermally and/or electrically insulating material and provide touch protection of the antenna relative to the local coil.

Furthermore, the housing has a transparent housing part, which is connected to a section of the antenna. The transparent housing part is designed to provide an unobstructed line-of-sight connection along a first straight line between the examined body region of the patient and the opening of the magnetic resonance apparatus and to avoid refraction and/or reflection of light along the first straight line. The transparent housing part is preferably made of a material which has as little absorption as possible for light in the human-visible range of the spectrum. The transparent housing part can likewise have as little absorption as possible of light in the near infrared range of the spectrum. Furthermore, it is conceivable for the material of the transparent housing part to absorb light as uniformly as possible in the human-visible range and in the near infrared range of the spectrum. Preferably, the material of the transparent housing part is furthermore non-magnetic. Materials which can be envisaged are glass or plastics, such as polycarbonate and polymethyl methacrylate. The material of the transparent housing part can also have a composite material, for example, in order to provide a scratch-resistant and/or static-conducting surface. For this purpose, the material of the transparent housing part can have, for example, a coating, a laminate or the like which does not significantly influence the optical properties of the transparent housing part. Possible coatings are plastics based on polysiloxanes, polyepoxides, polyurethanes, etc. The transparent housing part can have any shape. For example, it is conceivable for the transparent housing part to have a flat shell shape which is shaped according to a cylinder surface, a sphere surface or a facial region of the patient.

The section of the antenna connected to the transparent housing part can be, for example, a part of the antenna which is positioned in the field of view of the patient in an application-compliant position of the local coil at the patient. It is also conceivable that a section of the antenna is positioned at a diagnostically important body region of the patient. For this purpose, the antenna can be embedded in the transparent housing part, for example, or connected to the latter in terms of material, for example by means of an adhesive film or lamination.

Furthermore, the transparent housing part is designed to provide an unobstructed line-of-sight connection along a first straight line between the examined body region of the patient and the opening of the magnetic resonance apparatus and to avoid refraction and/or reflection of light along the first straight line. The opening of the magnetic resonance apparatus is preferably a passage through which the patient reaches the isocenter of the volume with the highest homogeneity of the magnetic field of the magnetic resonance apparatus. The opening can be, for example, the entrance of a cylindrical or C-shaped main magnet. It is conceivable to monitor a diagnostically important body region of the patient by means of a camera located outside and/or at the magnetic resonance apparatus. In this case, the camera can be directed through the opening of the magnetic resonance apparatus to a diagnostically important body region of the patient in order to detect a movement of the patient. In this case, a diagnostically important body region of the patient may be covered by the local coil, wherein the transparent housing part of the local coil is positioned such that an unobstructed line-of-sight connection from the diagnostically important body region to the camera is possible. The first line can be oriented along any point on the body region of diagnostic interest and on the surface of the camera, for example.

An unobstructed line-of-sight connection can mean that light falling onto the camera from a diagnostically important body region is absorbed, reflected or refracted by the transparent housing part to a small extent. For example, it is conceivable that at most 15%, at most 25% or at most 35% of the light passing through the transparent housing part is absorbed, reflected and/or refracted.

By providing a transparent housing part, an unobstructed line-of-sight connection between the diagnostically important body region covered by the local coil and the camera can be provided in an advantageous manner. In this way, the movement of the patient can be tracked during the magnetic resonance examination and used to correct image artifacts due to the movement.

In a possible embodiment of the local coil according to the utility model, the local coil is positioned in an application-compliant position at the head of the patient, wherein the transparent housing part is positioned in the field of view of the patient and is designed to provide an unobstructed line-of-sight connection along a second straight line, wherein the second straight line is oriented from the eye of the patient substantially orthogonally to the surface of the transparent housing part. In this embodiment, the local coil can be embodied as a head coil which is positioned at a section of the head of the patient and/or surrounds at least one section of the head on the outer circumference. Preferably, the antenna of the local coil is embedded not only in the transparent housing part, but also in the rest of the housing of the local coil and is positioned close to the head of the patient.

The field of view can include a region having a visual object that can be stared at by the patient's eyes in a static position of the head. It is conceivable for the transparent housing part to be positioned in a predetermined distance from the eye of the patient such that the field of view of the patient intersects the transparent housing part. The surface of the transparent housing part can be shaped substantially according to the surface contour of the head of the patient and/or oriented parallel to the surface contour of the head of the patient. The surface contour of the patient's head can be, for example, oval, circular or shell-shaped. It is likewise conceivable for the surface of the transparent housing part to have recesses and/or projections which model the shape of the face of the patient. The second line is oriented from the patient's eye substantially orthogonal to the surface of the transparent housing component. This can mean that the second straight line deviates from an orthogonal line of the surface of the transparent housing part by a maximum of 15%, a maximum of 25% or a maximum of 35%.

By providing the local coil with a transparent housing part in the field of view of the patient, the patient experience during a magnetic resonance examination can be improved and the number of interruptions due to claustrophobic patients is reduced in an advantageous manner. Furthermore, by means of the unobstructed line-of-sight connection along the second straight line, a sufficient line-of-sight contact of the patient with its surroundings can be achieved in an advantageous manner in a relatively resting position of the eye of the patient.

According to a further embodiment of the local coil according to the utility model, the antenna is positioned on a transparent printed circuit board, wherein the transparent printed circuit board is designed to reduce reflection and/or refraction of light impinging on the transparent printed circuit board. The antenna can be embodied as a conductor track, which is positioned on the electrically insulating material of the transparent printed circuit board. It is likewise conceivable for the conductor tracks to comprise a plurality of conductor tracks and/or antennas. The transparent printed circuit board is, for example, embodied as a strip or strip having a polygonal, elliptical or preferably rectangular cross-sectional shape. The material of the transparent printed circuit board can be flexible, so that the transparent printed circuit board can be shaped to match the shape of the transparent housing part. A suitable material group for the transparent conductor tracks is, for example, polyimide. However, transparent printed circuit boards can likewise have rigid or dimensionally stable materials. Preferably, the optical properties of the transparent conductor track are substantially matched to the material of the transparent housing part, so that refraction of light at the boundary surface between the transparent housing part and the transparent printed circuit board is avoided. It is desirable that the transparent printed circuit board has a cross section as small as possible. This can mean that the height and width of the transparent printed circuit board only slightly exceed the height and width of the conductor tracks of the antenna. Slight excesses can include, for example, a range of a few micrometers to several millimeters.

By using a transparent printed circuit board, the obstruction of the patient's field of view by the antenna positioned in the field of view can be reduced in an advantageous manner. Furthermore, an unobstructed line-of-sight connection between the facial area of the patient and the camera can be provided in an advantageous manner by using a transparent printed circuit board.

In a further embodiment of the local coil according to the utility model, the antenna has a metal line conductor which is designed to reduce obstruction of the light impinging on the antenna. As mentioned above, the metal line conductor can be a conductive metal line. It is also conceivable that the antenna has a plurality of metal line conductors. It is furthermore conceivable for the local coil to have a plurality of antennas with a plurality of metal wire conductors. The wire conductor can have any cross-sectional shape. Preferably, the metal wire conductor has a substantially circular cross-sectional shape. The maximum diameter of the wire conductor can be, for example, 0.5mm, 1mm, 2mm, 3mm, 4mm or 5mm in order to reduce obstruction of the light impinging on the antenna. It is also conceivable for the metal line conductors to have a coating or plating with silver or gold in order to reduce the resistance of the metal line conductors to the radio-frequency alternating current of the magnetic resonance signals. Here, a skin effect can be compensated, which describes the squeezing of the current density from the inside of the metal line conductor into the outer region of the metal line conductor. It is likewise conceivable that, instead of a solid conductor, the wire conductor has a plurality of strands, which are bundled to form the wire conductor. The metal wire conductor is preferably embedded and/or injected into the transparent housing part. It is also conceivable for the wire conductor to be mechanically connected to the transparent housing part or to be at least partially mechanically decoupled from the transparent housing part via the separating layer. The metal wire conductor or the plurality of metal wire conductors can be connected to the side of the transparent case member over the entire surface by an adhesive film or a connection layer.

By using a metal wire conductor, the obstruction of light at the antenna can be reduced in an advantageous manner. This increases the patient comfort and improves the line-of-sight connection to the diagnostically important body region of the patient. Furthermore, by using stranded or coated conductors, electrical losses and resistance along the antenna can be reduced. In this way, the heat development at the local coil can be reduced in an advantageous manner and the signal-to-noise ratio can be increased.

In a further embodiment of the local coil according to the utility model, the electronic component is positioned on a side of the local coil facing away from the field of view of the patient and/or on a side facing away from the opening of the magnetic resonance apparatus. In the case of a head coil, the side facing away from the patient's field of view can be the part of the housing which, in the application-compliant position of the local coil, for example at the head of the patient, is positioned at the back of the brain of the patient and/or laterally at the ears of the patient. It is conceivable that the housing has an opaque or translucent material on said side. Similarly, in the case of a surface coil, the side facing away from the opening of the magnetic resonance device can have an opaque or translucent material. The surface coil can be a local coil which is positioned in a planar manner along the surface of a diagnostically important body region of the patient. The surface coil can be positioned, for example, at the chest of the patient in a position that corresponds to the application. Preferably, the transparent housing part of the surface coil is positioned on the chest of the patient in such a way that an unobstructed line-of-sight connection between the surface of the chest and the opening of the magnetic resonance apparatus is ensured. In this case, the other parts of the housing of the surface coil can laterally bypass the patient and/or can laterally and/or posteriorly surround the torso of the patient. The part of the housing located at the patient on the lateral and/or rear side faces away from the opening of the magnetic resonance apparatus and can be embodied as opaque.

Preferably, the electronics of the local coil are positioned in a region of the housing which, in the application-compliant position of the local coil at the patient, points in a direction away from the opening of the magnetic resonance apparatus and/or the field of view of the patient. It is conceivable for the housing of the local coil to have an opaque material in this region.

By positioning the electronics in the region of the local coil facing away from the opening and/or the field of view of the magnetic resonance apparatus, blocking of the surface of the field of view and/or the body region of the patient by the electronics can be avoided in an advantageous manner.

According to a further embodiment of the local coil according to the utility model, the antenna is embedded in an unconstrained manner in the transparent housing part and is designed to reduce the transmission of pushing and/or bending forces between the antenna and the transparent housing part. Embedding the antenna in an unconstrained manner can mean that the antenna has one contact point, multiple contact points or contact faces with the transparent housing part, but is movable or positionable relative to the surface of the transparent housing part. It is conceivable for the antenna to have a housing, a separating layer and/or a cover which surrounds the antenna at least on one section on the outer circumference and has a low surface roughness and/or a low adhesion to the transparent housing part and/or the antenna. The housing or the separating layer can be embodied, for example, as a flexible hollow cylinder which is molded mechanically or using thermal energy onto the surface of the antenna or the printed circuit board. In particular, it is conceivable for the material of the antenna, of the housing, of the separating layer, of the coating and/or of the printed circuit board to have small molecular interactions with the transparent housing part. Thereby, the static friction and/or sliding friction between the antenna and the transparent housing part can be reduced.

By embedding the antenna in an unconstrained manner in the transparent housing part, the transmission of bending and/or pushing forces of the housing of the local coil to the antenna can be reduced in an advantageous manner when operating the local coil. The risk of antenna damage can thereby be reduced in an advantageous manner when operating the local coil.

In one possible embodiment of the local coil according to the utility model, the connection terminal electrically connecting the antenna to the electronics module has a compensation element which is designed to electrically connect the antenna and the electronics module movably relative to each other. The connection terminal can be any electrical connection between the antenna and the electronic component. The connection terminals can be embodied, for example, as solder contacts, adhesive contacts and/or as plug contacts, or the antenna can be connected to the electronic component in another manner material-flush, force-fitting and/or form-fitting. The compensation element can be an adapter or a transition between the antenna and the electronic component. The compensation element is designed to connect the antenna and the electronic component to each other in a movable manner. For this purpose, the compensating element can have, for example, a spring element, a bending element or a strain element which can be elastically deflected when receiving a force. An electrical connection between the antenna and the electronic component is maintained while compensating for the element offset. For this purpose, the compensation element can have, for example, springs, spring plates, meandering conductors on an electrical substrate or the like, which are electrically connected to the antenna and the electronic components. It is conceivable that the electrical contact between the antenna and the electronic component is maintained while changing the relative position of the antenna with respect to the electronic component by several micrometers to several millimeters. Preferably, the compensation element is connected to or embedded in an opaque portion of the housing and provides an electrical connection to the antenna of the transparent housing component.

By means of the compensation element, the antenna can be mechanically decoupled from the electronic component in an advantageous manner. In this way, fractures or cracks due to improper handling of the local coil can be advantageously avoided. Furthermore, by means of the compensation element, a mechanical decoupling of the transparent housing part from the opaque part of the housing can be provided. In this way, the risk of damage to the electrical connection of the antenna to the electronic component, for example due to different thermal expansions of the materials during the magnetic resonance examination, can be reduced in an advantageous manner.

In a preferred embodiment of the local coil according to the utility model, the transparent housing part is of one piece type and internal boundary surfaces in the material of the transparent housing part are avoided. The one-piece transparent housing part is preferably formed by a potting and/or a component. The one-piece transparent housing part can be cast, injected, extruded and/or melted, for example, around the antenna and has a substantially homogeneous material composition. It is likewise conceivable for the one-piece transparent housing part to be produced by means of a 3D printing method, an injection molding method or a laser sintering method, so that a homogeneous material composition of the material of the transparent housing part is obtained. A uniform material composition can, for example, mean a substantially uniform distribution of the molecular constituent components of the material. The homogeneous material composition preferably relates to the material of the transparent housing part. Correspondingly, the antenna embedded therein can have a different material composition than the transparent housing part. However, the antenna can also be connected to the surface of the one-piece transparent housing part by means of an adhesive film or as a laminate.

The embodiment of the transparent housing part in one piece advantageously avoids internal boundary surfaces that may occur, for example, if the transparent housing part is composed of a plurality of elements. In this way, refraction and/or reflection of light at the inner boundary surface can also be avoided, so that an unobstructed line of sight along the first straight line and/or the second straight line can be provided in an advantageous manner.

In a possible embodiment of the local coil according to the utility model, the transparent housing part has at least one first element and one second element, wherein the first element is connected to the second element in a material-fit manner on the surface, and wherein the connection surface between the first element and the second element is designed to avoid refraction and/or reflection of light. The first and second elements are preferably shaped and connected to each other on the connecting face such that they form the shape of the transparent housing part. The first and second elements can be formed in one piece or in one piece. As already mentioned, the antenna can be embedded in the first and second element or connected to the surface of the first and/or second element by means of an adhesive film or as a laminate, for example. The second component preferably has a material or material composition that is compatible with the first component.

The first element and the second element are materially connected to one another along a connection surface. The connecting surface can thus be a transition between two or more elements of the transparent housing part. The connection surface can also be a boundary surface between the first element and the second element. The connection surface is preferably designed to avoid reflection and/or refraction of light. This can mean, for example, that the first element, the second element and the connecting surface have a substantially uniform material composition. It is also conceivable to avoid refractive index variations along the connection surface between the first element and the second element. The connection surface preferably has a substantially flat extension.

The connection between the first element and the second element can be provided, for example, by means of ultrasonic welding, Laser transmission welding (Laser-durchtrahlschweii β en), thermal caulking (Hei β vertemmen), bonding by means of solvents (e.g. dichloromethane, acetone), etc. It is envisaged that the optical properties of the connection surface between the first and second elements substantially correspond to the optical properties of the first and/or second elements. This can mean that the connection surface between the first element and the second element only slightly impairs the visual field of the patient or the line-of-sight connection between the camera and the diagnostically important body region in the application-compliant position of the local coil at the patient. The connection surface that prevents refraction and/or reflection of light can optionally extend and/or be oriented in the transparent housing part.

The antennas of the first and second elements can be electrically connected to each other on the connection face. Such an electrical connection of the antennas of the first and second element can be made, for example, by means of adhesive contacts, plug contacts, or the like. Furthermore, it is conceivable for the antenna and/or the antennas to be connected to the first element and the second element by means of an adhesive film or as a laminate. However, the antennas of the first element and of the second element are preferably guided separately from one another into the opaque part of the housing and are connected there with the electronic components. It is conceivable that the transparent housing part has further elements, for example a third element or a fourth element, in addition to the first element and the second element.

By using a plurality of elements, the complex three-dimensional shape of the transparent shell can be composed in an advantageous manner of a first element and a second element, but also of further elements. In this way, the production effort for complex shapes of the transparent element, for example, shapes adapted to the facial region of the patient, can advantageously be reduced.

In a possible embodiment of the local coil according to the utility model, the connection surface between the first element and the second element is oriented along a parallel to the first straight line and/or the second straight line and is designed to reduce refraction and/or reflection of light along the first straight line and/or the second straight line. The orientation of the connection plane along a parallel line of the first straight line and/or of the second straight line can mean that the connection plane is oriented parallel to the first straight line and/or the second straight line during the magnetic resonance examination when the local coil is positioned at the patient in a suitable manner. However, it can also mean that the connection surface is oriented at a small inclination, for example at an angle of at most 10 °, at most 30 ° or at most 50 °, relative to the first straight line and/or the second straight line. In particular, it is conceivable for the connection surface to be oriented parallel to the first straight line, but to have an inclination relative to the second straight line. In addition to this, the connecting surface can also be oriented parallel to the second straight line and have a small inclination relative to the first straight line. Furthermore, a small first inclination relative to the first straight line, which is different from a small second inclination relative to the second straight line, is also conceivable. In this embodiment, the optical properties of the connection surface between the first element and the second element can be different from the optical properties of the material of the first element and/or the material of the second element. In this case, the line of sight is not obstructed, in particular by avoiding the intersection of the connecting surface with the first straight line and/or the second straight line.

By aligning the connection surface with the first straight line and/or the second straight line, an unobstructed line-of-sight connection along the first straight line and/or the second straight line can be ensured in an advantageous manner. In this way, the effort for providing an optically transparent connection surface between the first element and the second element and the production costs of the local coil can be advantageously reduced.

In a further embodiment of the local coil according to the utility model, at least the first element has a recess, wherein the antenna is positioned in the recess and is surrounded at the outer circumference at least along one section by the first element and the second element. The groove can be an elongated recess having any cross-section. Preferably, the cross-section of the groove is rectangular, elliptical or semi-elliptical. The cross section of the groove can likewise be matched to the cross section of the antenna, so that the cross section of the antenna fills the cross section of the groove over the entire surface or with a small gap. The small gap can have a dimension of 0.5mm, 1mm or 2mm between the surface of the antenna and the inner surface of the groove, for example. It is likewise conceivable for the antenna to have a housing, a coating and/or a separating layer which fills or reduces the size of the small gap with the inner face of the groove. Preferably, as mentioned above, the antenna is placed in the recess of the first element in an unconstrained manner. The groove can be positioned on a surface of the first element. Preferably, the groove is located along a connection face of the first element with the second element. It is also conceivable for the first and second elements to each have complementary recesses which, when the first and second elements are connected, are positioned one above the other and form channels extending along the connecting surface.

By means of the groove, the antenna can be positioned between the first element and the second element in an advantageous manner. This reduces the cost for embedding the antenna in the material of the first element.

In a possible embodiment of the local coil according to the utility model, the antenna has a capacitor and the recess has a recess, wherein the capacitor is positioned in the recess of the recess, and wherein the recess is designed to prevent transmission of pushing and/or bending forces between the transparent housing part and the capacitor. The clearance can be a recess or a cut-out along the groove of the first element. The hollow can have any cross-sectional shape. Preferably, the cross-sectional shape of the recess is adapted to the cross-section of the capacitor, so that the cross-section of the capacitor fills the cross-section of the recess over the entire surface or with a small gap. The recess can be embodied, for example, with a thickness of 30mm³To 8cm³Square or cubic cut-outs of the volume of (a). The capacitor can be, for example, a shortening capacitor that coordinates the antenna with a desired wavelength of the magnetic resonance signal. The capacitor can have a housing with a coating or a separating layer which has contact points or contact surfaces with the wall of the recess, but relative movement of the capacitor relative to the recess can be achieved. The relative movement is limited to the size of the small gap between the capacitor and the wall of the recess. Furthermore, it is conceivable that the free volume of the small gap between the capacitor and the wall of the recess has a dielectric with a low dielectric conductivity. Low dielectric conductivityThe medium is preferably a fluid, such as air, nitrogen or a noble gas.

By providing a recess in the recess for the antenna, the capacitor can advantageously be integrated in the housing of the local coil along the antenna. In addition, the dielectric loss in the transparent housing part can be advantageously reduced by providing a medium with low dielectric conductivity in a small gap. Furthermore, a small gap between the wall of the recess and the capacitor prevents the transmission of thrust and bending forces between the first element and the capacitor. In this way, mechanical loading of the capacitor and/or of the electrical connection of the capacitor to the antenna can be advantageously avoided.

In a possible embodiment of the local coil according to the utility model, the housing of the capacitor has a transparent material which is designed to reduce reflection and/or refraction of light impinging on the housing. In this case, the transparent material of the housing of the capacitor can be matched to the material of the transparent housing part, so that refraction of light at the interface of the transparent housing part and the housing of the capacitor is reduced and/or avoided. Preferably, the transparent material of the housing of the capacitor has a small dielectric conductivity in order to reduce dielectric losses. It is likewise conceivable for the housing of the capacitor to be filled with a dielectric having a small dielectric conductivity.

By using a transparent material for the housing of the capacitor, the obstruction of light by the capacitor along the first straight line and/or the second straight line can be reduced in an advantageous manner. Furthermore, by using a material having a small dielectric conductivity or filling the housing of the capacitor with a medium having a small dielectric conductivity, the dielectric loss of the local coil can be advantageously reduced.

In a further embodiment of the local coil according to the utility model, the housing has: at least one first housing element comprising a transparent housing part, a second housing element, and a holding mechanism, wherein the holding mechanism mechanically connects the first housing element and the second housing element to each other and holds them in a predetermined relative position with respect to each other. The holding means can be any molded structure that connects the first housing element and the second housing element to one another in a force-fitting and/or form-fitting manner. Conceivable embodiments of the holding mechanism include, for example, hinges, clamps, locking elements, plug elements, hinges, rail elements, hook-and-loop elements, etc. The holding mechanism is preferably designed to fix the first housing part and the second housing part in different relative positions with respect to one another and/or to enable a continuous transition between the two relative positions. In one example, the first housing part and the second housing part can be connected to each other via a hinge, wherein the hinge can enable a plurality of opening angles between the first housing part and the second housing part. The first housing part has a transparent housing part. It is likewise conceivable for the first housing part to correspond to the transparent housing part. The second housing part is preferably positioned on the side of the local coil facing away from the patient's field of view and/or the side facing away from the opening of the magnetic resonance apparatus and can comprise an opaque material. It is likewise conceivable for the electronic assembly to be positioned at the second housing part or to be embedded in the second housing part.

In one example, the first housing part and the second housing part have electrical contacts which are implemented complementary to one another and which, in the closed state of the local coil, electrically connect the antenna with the electronic assembly. The contacts can be embodied, for example, as complementary plug elements which electrically and mechanically connect the electrical contacts of the antenna to the electrical contacts of the electronic assembly and which release when the first housing part is detached or opened from the second housing part. However, it is also conceivable for the electrical connection between the antenna and the electronic assembly to be embedded in the housing independently of the retaining mechanism and to be maintained when the first housing part is detached or opened from the second housing part.

In particular, it is conceivable that the first housing part, the second housing part and the holding means are designed such that a passage for positioning a diagnostically important body region of a patient in the local coil can be provided by separating or opening the first housing part and the second housing part by means of the holding means.

By using the holding mechanism, the first housing part and the second housing part can be separated and/or opened from each other in an advantageous manner. This simplifies the introduction of the diagnostically important body region or body part of the patient into the local coil and increases the patient comfort.

According to a further embodiment of the local coil according to the utility model, the transparent housing part has ventilation openings which are designed to support the transport of breathing air into the local coil and/or the transport of thermal energy from the examined body region to the surrounding medium. The transparent housing part can have any number of ventilation openings. The ventilation opening can have any shape, for example an oval or polygonal shape. Preferably, the shape of the ventilation opening is adapted to the position or orientation of the antenna or the arrangement of the antenna in the transparent housing part, so that an intersection of the antenna with the ventilation opening is avoided. The ventilation opening can be located, for example, close to the mouth region and/or the nose region of the patient in order to simplify the delivery of breathing air to the patient. The ventilation opening can also be designed to enable heat transfer from the surface of the patient to the surrounding medium, for example air. The heat transfer can take place by means of a natural convection process which transports away the heated volume elements of the air from the surface of the patient and replaces them by cooler volume elements. It is furthermore conceivable that other parts of the housing, for example positioned at the back of the brain or ear of the patient, have ventilation openings.

By providing the ventilation opening, the delivery of breathing air to the patient is improved in an advantageous manner in an application-compliant position of the local coil at the patient. Furthermore, heating up of the local coil and/or of the examined body region of the patient during the magnetic resonance examination can be advantageously counteracted by means of natural convection processes.

The magnetic resonance system according to the utility model comprises a magnetic resonance device and a local coil according to the utility model, wherein the local coil is electrically connected to the magnetic resonance device via an electrical connection, and wherein the electrical connection is designed to establish a signal connection between the local coil and the magnetic resonance device. The electrical connection line can be, for example, a coaxial cable with a shield in order to avoid electromagnetic dispersion from the surroundings. The electrical connection line is preferably connected to a corresponding physical interface of a receiver at the magnetic resonance apparatus. The magnetic resonance system can have a receiving channel or a plurality of receiving channels, which filter and/or digitize the received signals and transmit them to an evaluation unit having a processor. The evaluation unit is preferably designed to determine an image or a spectrum based on the received signals and to output the image or spectrum to a user of the magnetic resonance apparatus via the display unit.

In particular, it is conceivable for the local coil to have an arrangement of antennas, the received magnetic resonance signals of which are simultaneously transmitted to the magnetic resonance device by means of the electrical connection. The magnetic resonance apparatus can have a switching matrix which selects the activated receiving channels depending on the body region of the patient to be examined.

The utility model has the advantage that, by using a switching matrix between the local coil and the magnetic resonance system, signals of the following antennas can be transmitted exclusively from the plurality of antennas of the local coil to the magnetic resonance system: the antenna is positioned in the direct vicinity of a diagnostically important body region of a patient.

Drawings

Further advantages and details emerge from the following description of an embodiment with reference to the drawings. In the principle view, it is shown that:

figure 1 shows a possible embodiment of a magnetic resonance system according to the utility model,

figure 2 shows one possible embodiment of a local coil according to the utility model,

figure 3 shows one possible embodiment of a local coil according to the utility model,

figure 4 shows one possible embodiment of a local coil according to the utility model,

figure 5 shows a possible embodiment of a local coil according to the utility model,

figure 6 shows a possible embodiment of a transparent housing part of a local coil according to the utility model,

figure 7 shows a possible embodiment of a transparent housing part of a local coil according to the utility model,

figure 8 shows a possible embodiment of the transparent housing part of the local coil according to the utility model,

fig. 9 shows a possible embodiment of a holding mechanism for a local coil according to the utility model.

Detailed Description

Fig. 1 shows a schematic illustration of an embodiment of a magnetic resonance system with a magnetic resonance system 10, a local coil 26 and electrical connections 27. The magnetic resonance apparatus 10 comprises a magnet unit 11, for example with a permanent magnet, an electromagnet or a superconducting main magnet 12 for generating a strong and in particular homogeneous main magnetic field 13. Furthermore, the magnetic resonance apparatus 10 comprises a patient receiving region 14 for receiving a patient 15. In the present exemplary embodiment, the patient receiving region 14 is cylindrical and is surrounded in the circumferential direction by the magnet unit 11. In principle, however, other embodiments of the patient receiving region 14 are also conceivable, which differ from the example described.

A patient can be positioned in the patient receiving region 14 by means of a patient support device 16 of the magnetic resonance apparatus 10. For this purpose, the patient support device 16 has a table 17 which is designed to be movable within the patient receiving region 14. Furthermore, the magnet unit 11 has gradient coils 18 for generating magnetic field gradients, which are used for spatial encoding during imaging. The gradient coils 18 are controlled by means of a gradient control unit 19 of the magnetic resonance apparatus 10. Furthermore, the magnet unit 11 can comprise a radio-frequency antenna which in the present exemplary embodiment is designed as a body coil 20 which is fixedly integrated into the magnetic resonance apparatus 10. The body coil 20 is designed for exciting nuclei in the main magnetic field 13 generated by the main magnet 12. The body coil 20 is operated by a radio-frequency unit 21 of the magnetic resonance apparatus 10 and emits radio-frequency signals into an examination space which is formed substantially by the patient receiving region 14 of the magnetic resonance apparatus 10. The body coil 20 is also configured to receive magnetic resonance signals.

For controlling the main magnet 12, the gradient control unit 19 and for controlling the radio frequency unit 21, the magnetic resonance apparatus 10 has a control unit 22. The control unit 22 is designed to control the execution of a sequence, for example an imaging gradient echo sequence or a TSE sequence. Furthermore, the control unit 22 comprises an evaluation unit 28 for evaluating the digitized magnetic resonance signals detected during the magnetic resonance examination.

Furthermore, the magnetic resonance apparatus 10 comprises a user interface 23 with a signal connection to the control unit 22. The control information, e.g. the imaging parameters and the reconstructed magnetic resonance image, can be displayed for the user on a display unit 24 of the user interface 23, e.g. on at least one monitor. Furthermore, the user interface 23 has an input unit 25, by means of which parameters of the magnetic resonance measurement can be input by a user.

In the example shown, the local coil 26 is positioned at the head of the patient 15 and is connected with an electrical connection line 27. The electrical connection 27 provides a signal connection to a corresponding receiving channel of the radio-frequency unit 21 or of the control unit 22 of the magnetic resonance apparatus 10. The receiving channel filters and digitizes the signals received by the local coil 26 and transmits the data to an evaluation unit 28, which derives an image or a spectrum from the data and provides it to the user via the display unit 24.

Furthermore, the magnetic resonance apparatus 10 has an opening 31 through which the patient 15 is introduced into the magnetic resonance apparatus 10. In this case, a diagnostically relevant body region of the patient 15, for example the head, can be positioned in the isocenter 29 of the magnetic resonance apparatus 10. The magnetic resonance system can have a camera 34 which is aligned along a first line 32 with the head of the patient in order to monitor the movement and/or the position of the head in the magnetic resonance apparatus 10. The first straight line 32 preferably runs parallel to a plane formed by the y-direction and the z-direction. The camera 34 can be, for example, a 2D camera, a 3D camera, or the like. The local coil 26 has a transparent housing part 41 which enables an unobstructed line-of-sight connection for the patient along the second straight line 33. The transparent housing part 41 is preferably designed to provide an unobstructed line-of-sight connection along the first line 32 and the second line 33.

Fig. 2 shows a possible embodiment of a local coil 26 according to the utility model. The local coil 26 is embodied in the example shown as a head coil, which is able to accommodate the head of the patient 15 in a volume partially enclosed by the housing 45. The transparent housing part 41 has a plurality of antennas 42 which receive the magnetic resonance signals of the head of the patient 15 and forward them to the electronics 51. For this purpose, the antenna 42 can be electrically connected to the electronic component 51, for example, by means of plug contacts 52. It is conceivable for such plug contacts 52 to simultaneously serve as retaining means 58, which connect and hold the transparent housing part 41 to the rest of the housing 45. The electronic assembly 51 is preferably embedded in an opaque portion of the housing 45. Thereby, in the position in which the local coil 26 is conformed to the application at the head of the patient 15, the electronics assembly 51 is positioned outside the field of view of the patient 15. Furthermore, an unobstructed line-of-sight connection of the patient 15 along a second straight line 33 (y-direction) is ensured, which is oriented substantially orthogonally to the surface of the transparent housing part 41, starting from the eye of the patient. Of course, the illustrated embodiment serves only as a schematic sketch and can have, in use, particularly rounded edges and contours adapted to the shape of the head of the patient 15. The opaque part of the housing 45 can in particular have a further antenna 42 which is preferably embedded in the housing and is not shown in fig. 2.

Fig. 3 shows a further embodiment of a local coil 26 according to the utility model. In the example, the transparent housing part 41 has a first element 53 and a second element 54, which are connected to one another along the connecting surface 47 in a material-fitting manner. Preferably, the antenna 42 is arranged in the transparent housing part 41 such that the antenna 42 is prevented from crossing or overlapping the connection face 47. The connection surface 47 is preferably planar and oriented along a parallel line to the first straight line 32 in order to ensure an unobstructed line-of-sight connection of the camera 34 with the facial area of the patient 15.

Fig. 4 shows a further embodiment of a local coil 26 according to the utility model, in which the first element 53 and the second element 54 are connected to one another in a material-fit manner along their main surfaces, i.e. the side portions with the largest area. The optical properties of the connection surface 47 are substantially matched to the optical properties of the first element 53 and the second element 54, so that refraction and/or reflection of light on the connection surface 47 is avoided and an unobstructed line-of-sight connection between the patient 15 and the camera 34 can be ensured. The antennas 42 are positioned in respective recesses 55 positioned on a side of the first element 53 facing the second element 54. The antenna 42 is inserted in an unconstrained manner into the recess 55 and is surrounded on the outer circumference by the first element 53 and the second element 54 at least along sections on the transparent housing part 41. In the example shown, the antennas 42 of the local coil 26 are arranged in a grid-like manner in the transparent housing part 41 and are electrically connected in pairs to the electronic components 51. It is also contemplated that each antenna 42 is electrically connected to exactly one electronic component 51. However, more or all of the antennas 42 can also be connected to the electronic assembly 51. Furthermore, the embodiment of the local coil 26 shown in fig. 4 has ventilation openings 46 in the transparent housing part 41, which provides free space for the nose of the patient 15 and improves the air supply into the volume partially enclosed by the housing 45. In addition to the ventilation openings 46 shown, the local coil 26 can of course also have further ventilation openings 46 with any desired shape, which can be distributed at will on the transparent housing part.

Fig. 5 shows a further embodiment of a local coil 26, which is embodied as a surface coil. In this embodiment, the local coil 26 can rest against the surface of the chest or abdomen of the patient 15 in an application-appropriate position, for example. The embodiment shown in fig. 5 is to be understood as corresponding to a different view than the purely schematic view. The local coil 26 can have, for example, an arch or a curve that matches the body contour of the patient 15. In the example shown, two opaque parts of the housing 45 are on either side of the transparent housing part 41, in which the electronic components 51 are embedded. It is likewise conceivable for the opaque part of the housing 45 to be positioned on only one side of the local coil 26. Furthermore, the housing 45 can be completely transparent and avoid opaque parts of the housing 45. In this case, the electronic module 51 is embedded in the transparent housing part 41 with a lateral offset in order to ensure an unobstructed line-of-sight connection of the camera 34 to the body region of diagnostic importance. The four antennas 42 of the local coil 26 are embodied in fig. 5 as side-by-side loops which enclose the ventilation opening 46. In addition to the illustrated arrangement of the antenna 42, of course any further arrangement of the antenna 42 is conceivable. The four ventilation openings 46 support the transport of thermal energy away from the surface of the patient 15 by means of a passive convection process. The ventilation openings 46 can be shaped arbitrarily and have any number.

Fig. 6 shows a possible embodiment of a transparent housing part 41 of a local coil 26 according to the utility model. In the example, the antenna 42 of the local coil 26 is embodied as a metal wire conductor surrounded on the outer circumference by a transparent housing part 41. The metal line conductors of the antenna 42 have a separating layer 48, which separates them from the transparent housing part 41. The separating layer 48 can be movably embedded in the transparent housing part 41 or mechanically connected thereto. The wire conductors of the antenna 42 are preferably embedded in the transparent casing 41 without constraint. This can mean that the metal wire conductor is at least movable relative to the separation layer 48 and has a small molecular interaction or a small adhesion force with the separation layer 48 in order to reduce static and sliding friction forces along the separation layer 48. The transparent housing part 41 is embodied in one piece in the example shown. Before the material of the transparent housing part 41 hardens, the wire conductors of the antenna 42 can be encapsulated, injected or dipped together with the separating layer 48 in a melt of the material of the transparent housing part 41 in predetermined positions, for example.

Fig. 7 shows a further embodiment of a transparent housing part 41 of a local coil 26 according to the utility model. In the example shown, the transparent housing part 41 has a first element 53 and a second element 54 which are connected to one another in a material-fitting manner along the connecting surface 47. The first and second elements 53, 54 each have a groove 55 with a semicircular cross section, which, when the first element 53 is connected to the second element 54 in a suitable manner, are positioned one above the other and result in a channel with a circular cross section. The wire conductor of the antenna 42 is embedded in and surrounded by the channel between the first element 53 and the second element 54 at the outer circumference. It is envisaged that a small gap 56 between the wire conductor of the antenna 42 and the wall of the first element 53 and/or the second element 54 is filled by the separation layer 48. However, the wire conductors of the antenna 42 can likewise be placed unconstrained in the grooves 55. It is furthermore conceivable for the recess 55 to be provided only on the first element 53 or the second element 54 and to have a cross section which is matched to the cross section of the wire conductor of the antenna 42. It is likewise conceivable for a printed circuit board 57 with conductor tracks to be embedded in the recesses 55 of the first element 53 and/or of the second element 54 instead of the wire conductors.

Fig. 8 shows an embodiment of the transparent housing part 41 of the local coil 26 according to the utility model, wherein the second element 54 has a recess 49 for accommodating the capacitor 43. In the example shown, the printed circuit board 57 is positioned in the recess 55 of the second element 54 and is surrounded on the outer circumference by the first element 53 and the second element 54. The printed circuit board 57 has a capacitor 43 which protrudes from the printed circuit board 57 in a direction towards the second element 54. In order to compensate for the height difference between the capacitor 43 and the printed circuit board 57, the second element 54 has a recess 49 in which the capacitor 43 is positioned. It is conceivable that a small gap 56 exists between the outer shell of the capacitor 43 and the wall of the second element 54 (inner face of the recess), which gap is filled with air or an inert gas in order to reduce dielectric losses. In one possible embodiment, the housing 44 of the capacitor 43 and the printed circuit board 57 are constructed of a transparent material.

Fig. 9 shows a possible embodiment of a holding mechanism 58 for a local coil 26 according to the utility model. The holding means 58 is embodied in the example shown as a rail system which movably supports and holds together the first housing element 61 and the second housing element 62 relative to one another. The first housing element 61 is essentially formed by a transparent housing part 41 which is shaped to imitate the facial area of the patient 15. The second housing member 62 is positionable at the posterior cranium of the patient 15 and at the ears of the patient 15 and is preferably constructed of an opaque material. The head of patient 15 rests on pillow 63, which provides a soft cushion and avoids compression sites at the posterior cranium of patient 15. The rail system can have, for example, a guide bar and a slide which engages into a recess of the guide bar and is movable along the recess. The guide strip and the slide are positioned here on the side of the first housing element 61 and the second housing element 62 facing each other. Preferably, the first housing element 61 is movable in the axial direction (z-direction) relative to the second housing element 62 by means of a rail system in order to provide or simplify access for the head of the patient 15. In addition to the rail system, for example, hinges, flaps or any other of the above-described retaining mechanisms are conceivable.

In the embodiment shown in fig. 9, the transparent housing part 41 of the first housing element 61 consists of four elements. The connection surface 47 between these elements is oriented substantially perpendicularly to the surface of the transparent housing part 41 facing away from the patient 15 and parallel to the first line 32. The two outer connection faces 47 of the transparent housing part 41 are angled or inclined with respect to the parallel of the second straight line 33. Thereby, the field of view of the patient 15 can be expanded and patient comfort improved.

Although the details of the present invention have been shown and described in detail with respect to preferred embodiments thereof, the utility model is not limited by the disclosed examples and other modifications can be derived therefrom by those skilled in the art without departing from the scope of the utility model.

Claims (16)

1. A local coil (26) for receiving radio frequency signals in a frequency and power range of a magnetic resonance apparatus (10), the local coil comprising: an antenna (42); an electronic component (51) electrically connected to the antenna (42); and a housing (45) which is shaped according to a body region of a patient (15) and which surrounds the electronics assembly (51) and the antenna (42) on the outer circumference,

it is characterized in that the preparation method is characterized in that,

the housing (45) has a transparent housing part (41) which is connected to a section of the antenna (42) and is designed to provide an unobstructed line-of-sight connection between the examined body region of the patient (15) and the opening (31) of the magnetic resonance device (10) along a first straight line (32) and to avoid refraction and/or reflection of light along the first straight line (32).

2. The local coil (26) according to claim 1,

wherein the local coil (26) is positioned at the head of the patient (15) in an application-compliant position, wherein the transparent housing part (41) is positioned in the field of view of the patient (15) and is designed to provide an unobstructed line-of-sight connection along a second straight line (33), wherein the second straight line (33) is oriented substantially orthogonal to the surface of the transparent housing part (41) starting from the eye of the patient (15).

3. The local coil (26) according to claim 1 or 2,

wherein the antenna (42) is positioned at a transparent printed circuit board (57), wherein the transparent printed circuit board (57) is designed for reducing reflection and/or refraction of light impinging on the transparent printed circuit board (57).

4. The local coil (26) according to claim 1 or 2,

wherein the antenna (42) has a metal wire conductor designed to reduce obstruction of light impinging on the antenna (42).

5. The local coil (26) according to claim 1 or 2,

wherein the electronics assembly (51) is positioned on a side of the local coil (26) facing away from a field of view of the patient (15) and/or on a side facing away from an opening (31) of the magnetic resonance apparatus (10).

6. The local coil (26) according to claim 1 or 2,

wherein the antenna (42) is embedded in the transparent housing part (41) in an unconstrained manner and is designed to reduce the transmission of pushing and/or bending forces between the antenna (42) and the transparent housing part (41).

7. The local coil (26) according to claim 1 or 2,

the connection end, which electrically connects the antenna (42) to the electronic component (51), has a compensation element, which is designed to electrically connect the antenna (42) and the electronic component (51) movably relative to one another.

8. The local coil (26) according to claim 1 or 2,

wherein the transparent housing part (41) is one-piece and avoids internal boundary surfaces in the material of the transparent housing part (41).

9. The local coil (26) according to claim 2,

wherein the transparent housing part (41) has at least one first element (53) and a second element (54), wherein the first element (53) is connected to the second element (54) in a material-fit manner on the surface, and wherein a connection surface (47) between the first element (53) and the second element (54) is designed to avoid refraction and/or reflection of light.

10. The local coil (26) according to claim 9,

wherein a connection surface (47) between the first element (53) and the second element (54) is oriented along a parallel to the first straight line (32) and/or a parallel to the second straight line (33) and is designed for reducing refraction and/or reflection of light along the first straight line (32) and/or the second straight line (33).

11. The local coil (26) according to claim 9,

wherein at least the first element (53) has a groove (55), wherein the antenna (42) is positioned in the groove (55) and is surrounded circumferentially by the first element (53) and the second element (54) at least along one section.

12. The local coil (26) according to claim 11,

wherein the antenna (42) has a capacitor (43) and the recess (55) has a recess (49), wherein the capacitor (43) is positioned in the recess (49) of the recess (55), and wherein the recess (49) is configured to avoid transmission of pushing and/or bending forces between the transparent housing part (41) and the capacitor (43).

13. The local coil (26) according to claim 12,

wherein a housing (44) of the capacitor (43) has a transparent material which is designed to reduce reflection and/or refraction of light impinging on the housing (44).

14. The local coil (26) according to claim 1 or 2,

wherein the housing (45) has: at least one first housing element (61) comprising the transparent housing part (41), a second housing element (62), and a holding mechanism (58), wherein the holding mechanism (58) mechanically connects the first housing element (61) and the second housing element (62) to each other and holds them in a predetermined relative position to each other.

15. The local coil (26) according to claim 1 or 2,

wherein the transparent housing part (41) has ventilation openings (46) which are designed to support the supply of breathing air to the local coil (26) and/or the transfer of thermal energy from the examined body region to the surrounding medium.

16. A magnetic resonance system comprising a magnetic resonance device (10) and a local coil (26) according to one of claims 1 to 15, wherein the local coil (26) is electrically connected with the magnetic resonance device (10) via an electrical connection line (27),

it is characterized in that the preparation method is characterized in that,

the electrical connection (27) is designed to establish a signal connection between the local coil (26) and the magnetic resonance device (10).

Images