Dental coil and magnetic resonance device for imaging a jaw region

Description

[0001] The invention relates to a dental coil configured to receive high-frequency signals in a frequency and power range of a magnetic resonance measurement of a patient's jaw region. Furthermore, the invention relates to a magnetic resonance device having a dental coil, wherein the magnetic resonance device is configured to perform imaging of a patient's jaw region.

[0002] Diseases of the teeth and periodontium, such as caries or periodontitis, are now commonly diagnosed using X-ray-based imaging techniques. Conventional or digital X-ray projection techniques are primarily used, as are recently also three-dimensional X-ray techniques. One example of a three-dimensional X-ray technique is digital cone beam tomography, which can be used to image teeth and the viscerocranium.

[0003] A major disadvantage of X-ray techniques is the necessity of using ionizing radiation for imaging. One imaging technique that avoids ionizing radiation is magnetic resonance imaging. This typically enables better soft tissue contrast than X-ray techniques and supports three-dimensional imaging of an examination subject as standard. Furthermore, magnetic resonance imaging enables the imaging of cysts and the detection of dentin degradation before this can be detected by X-ray techniques. Magnetic resonance imaging thus represents a potential alternative to conventional X-ray techniques for imaging a dentition and / or jaw region, as well as for diagnosing dental diseases in the examination subject.

[0004] Magnetic resonance imaging is a well-known imaging technique used to create magnetic resonance images of the interior of an examination subject. During magnetic resonance imaging, the examination subject is typically positioned in a strong, static, and homogeneous basic magnetic field (B0 magnetic field) of a magnetic resonance scanner. The basic magnetic field can have magnetic field strengths ranging from 0.2 Tesla to 7 Tesla, causing the nuclear spins of the examination subject to align along the basic magnetic field. To trigger so-called nuclear magnetic resonances, high-frequency signals, called excitation pulses (B1 magnetic field), are radiated into the examination subject. Each excitation pulse causes a deviation of the magnetization of certain nuclear spins of the examination subject from the basic magnetic field by an amount known as the flip angle.An excitation pulse can comprise an alternating magnetic field with a frequency corresponding to the Larmor frequency at the respective static magnetic field strength. The excited nuclear spins can exhibit a rotating and decaying magnetization (nuclear magnetic resonance), which can be detected as a magnetic resonance signal using special antennas. For spatial encoding of the nuclear magnetic resonances of the object under investigation, magnetic gradient fields can be superimposed on the basic magnetic field.

[0005] The received magnetic resonance signals are typically digitized and stored as complex values in a k-space matrix. This k-space matrix can be used as the basis for reconstructing magnetic resonance images and determining spectroscopic data. Reconstruction of a magnetic resonance image is typically performed using a multidimensional Fourier transform of the k-space matrix.

[0006] Because it avoids ionizing radiation, magnetic resonance imaging is particularly suitable for continuous diagnostic monitoring of dental diseases and / or tooth development within the framework of a longitudinal imaging study. Longitudinal imaging studies typically involve multiple imaging examinations to determine the progression of a disease or the success of therapeutic treatment over a predetermined period of time. However, diagnostically relevant areas of a patient's jaw region, such as an oral cavity, dentition, dental arch, or tooth, provide a small volume available for generating magnetic resonance signals. Furthermore, conventional volume and surface coils, such as head coils and contact coils, are located at a relatively large distance from the diagnostically relevant area.However, a large distance can increase the signal-to-noise ratio of acquired magnetic resonance signals and thus reduce the quality of reconstructed magnetic resonance images of the patient's dentition.

[0007] The document "Mandibula 15-Channel Dental Coil - Noras MRI Products", Internet, 2017, pages 1-74, XP055980776, URL: https: / / docplayer.org / 132670679-Mandibula-15-kanal-dental-spule-1-5t-si-t-si.html, describes a 15-channel dental coil for imaging the jaw, teeth, and pulp.

[0008] The document EP 3 489 704 A1 relates to a local MRI coil with at least two coil elements for a dental MRI measurement of a patient’s head.

[0009] US 2012 / 288820 A1 describes an MRI system with a radiofrequency coil unit. The radiofrequency coil unit can be attached to a portion of a patient in a contact-free or non-contact manner and enables reception of an MR signal from that portion of the patient.

[0010] The document JP H03 29639 A discloses a local coil which is made integrally from a conductive coil and a shape memory material and allows free bending for adaptation to an external shape of a test person.

[0011] It is therefore an object of the invention to provide a dental coil which enables the acquisition of high-quality magnetic resonance images of the patient's jaw region.

[0012] This object is achieved according to the invention by the subject matter of the independent patent claim. Advantageous embodiments and expedient further developments are the subject matter of the dependent claims.

[0013] The dental coil according to the invention comprises a first element, wherein the first element consists of a dimensionally stable material and comprises a recess which is suitable for receiving a mouth region and / or a nose region of a patient when the dental coil is positioned on a jaw region of the patient as required.

[0014] A rigid material can be any material that exhibits negligible deformation when the dental coil is positioned as intended on a patient's jaw region. Preferably, the rigid material exhibits the lowest possible interaction with magnetic fields, so that the first element is essentially undetectable for magnetic resonance imaging. Examples of suitable rigid materials include plastics such as silicones, polyesters, and polycarbonates, as well as various ceramics such as aluminum oxide or zirconium oxide. Other materials, such as glass or glass-fiber-reinforced plastics, are of course also possible. The recess in the first element can be a hole or opening that allows the patient to breathe and / or ventilate the mouth and / or nasal region when the dental coil is positioned as intended on the jaw region.The first element can be understood in particular as a frame which encloses the mouth and / or nose region of the patient and / or simplifies positioning of the dental coil on the jaw region of the patient.

[0015] The dental coil according to the invention further comprises a second element, wherein the second element has a flexible element which is designed to enable reshaping of the jaw region of the patient by means of the flexible element.

[0016] A flexible element is preferably reversibly deformable. The second element can be made integrally from the flexible element or have segments that enable reversible deformation of the flexible element. A segment of the flexible element can, for example, represent a hinge, a joint, a bearing, or the like. It is conceivable for the flexible element to be reversibly deformable by means of a segment. The segment can comprise an elastic and / or a rigid material.

[0017] The flexible element preferably comprises a plastically or elastically preformable material. The flexible element can also be made entirely of a plastically or elastically deformable material. Examples of such materials are plastics such as polyethylene, polyurethane, polyamide, and polyester. Naturally based materials such as rubber or fiber materials are also conceivable. In a preferred embodiment, the flexible element is designed as a foam, fiber material, or the like in order to achieve a low density and thus a low weight. The flexible element can be deformed such that the second element can be shaped to fit the individual geometries of a plurality of different jaw regions of different patients. In a preferred embodiment, the flexible element can be deformed by means of manual force applied by an operator of a magnetic resonance device or by the patient.Reshape the patient's jaw region using the flexible element can, in particular, involve deforming and / or adapting a surface contour of the second element. The second element can be brought into contact with a skin surface of the jaw region (e.g., by pressing it on). However, it is also conceivable for the second element to reshape the patient's jaw region without contact with the skin surface.

[0018] In a proper application position of the dental coil on the patient's jaw region, the second element can be aligned substantially tangentially to a cheek of the patient, in particular parallel to a row of adjacent molars of the patient. The second element can furthermore have a curvature that mimics a curvature of the cheek and / or a portion of the patient's dental arch.

[0019] The dental coil according to the invention is particularly designed to position and / or hold the first element and the second element simultaneously on the patient's jaw region. This allows magnetic resonance signals from the jaw region to be acquired using the first element and the second element as part of a magnetic resonance measurement of the patient's jaw region.

[0020] The first element and the second element of the dental coil according to the invention have an antenna which is designed to receive high-frequency signals in a frequency and power range of a magnetic resonance measurement.

[0021] An antenna can represent a coupling element between electromagnetic waves guided in signal conductors and unguided, i.e., free-space, electromagnetic waves. The antenna is particularly designed to receive electromagnetic waves in the range of a magnetic resonance frequency of a magnetic resonance-active atomic nucleus. Electromagnetic waves relevant for magnetic resonance measurements can be radio-frequency signals or magnetic resonance signals, which comprise frequencies between 1 and 500 MHz, preferably between 10 and 300 MHz. The magnetic resonance signals of typical atomic nuclei to be examined can have a low power of a few microwatts to several milliwatts.

[0022] A signal conductor is preferably an electrically conductive wire. The signal conductor wire can have an oval or polygonal cross-section and be suitable for continuously transmitting the power specified above. It is also conceivable for the signal conductor to be designed as a conductor track on a circuit board and have an approximately rectangular cross-section. The signal conductor can be made of copper. However, other electrically conductive metals, such as gold or aluminum, are also conceivable.

[0023] The antenna of the dental coil according to the invention preferably has a contact guard, which protects an examination subject from voltages and / or burns. The signal conductor of the antenna can, for example, have a coating and / or a plastic cladding for this purpose. Suitable plastics include, for example, polytetrafluoroethylene (PTFE) or various polysiloxanes. Upon receiving a magnetic resonance signal, a current can be induced in the signal conductor, which can be transmitted to a magnetic resonance device via a suitable electrical connection cable. Such an electrical connection cable can, for example, be a coaxial cable with a shield to prevent electromagnetic interference from the environment.

[0024] It is conceivable that the dental coil has an electronic circuit connected to the antenna. The electronic circuit can comprise a single electronic component or a combination of several electronic components, such as transistors, resistors, capacitors, diodes, conductor tracks, and the like. The electronic circuit can, in particular, have a protective circuit suitable for protecting the antenna against overload. To avoid magnetic attraction forces, standing waves, heating, and similar undesirable effects, the electronic circuit can have a high proportion of non-magnetic materials as well as corresponding sheath wave barriers and / or baluns. The electronic circuit preferably has a printed circuit board (PCB) or a similar substrate suitable for accommodating the electronic components in a predetermined position relative to one another.

[0025] Of course, the dental coil according to the invention can comprise multiple antennas according to an embodiment described above. The antennas can be spaced apart from one another, adjacent to one another, or partially overlapping. The antennas can also be arranged in the form of a grid or a matrix. For example, the first element can have a first antenna or a first number of antennas, while the second element can have a second antenna or a second number of antennas.

[0026] It is further conceivable for the dental coil according to the invention to have at least one antenna designed to emit a high-frequency signal in a direction of the examination object, such as a jaw region of the patient. Depending on the basic magnetic field of a magnetic resonance device, the high-frequency signal emitted by the at least one antenna can, for example, be in a power range from a few watts to several kilowatts. The high-frequency signal emitted by the at least one antenna can, in particular, represent a B1 magnetic field. A part of the dental coil with the at least one antenna can, for example, represent a transmitting unit of the dental coil.

[0027] In a preferred embodiment, the first element comprises a number of antennas configured to receive magnetic resonance signals from a jaw region of the patient. The number of antennas may be integrated and / or embedded in the first element or carried by it. The rigid material of the first element may be configured to provide contact protection for the patient according to an embodiment described above.

[0028] A recess can be an oval or polygonal cutout in the first element. The recess is preferably characterized by a section of the first element that is free of signal conductors. The recess can, in particular, be designed to provide a free space for a nose and / or mouth of the patient when the dental coil is positioned in a suitable position for performing a magnetic resonance measurement on the patient's jaw region. Contact between the nose and / or mouth of the patient and the first element can thus be avoided. In a preferred embodiment, the antenna or antennas of the first element are arranged such that the recess is free of signal conductors. For this purpose, the antenna or antennas can surround the recess in a loop-like manner, for example. The first element can have one or more recesses.For example, the first element may have a first recess for the patient's nose and a second recess for the patient's mouth. However, it is also conceivable for the first element to have a single recess that can accommodate both the patient's nose and mouth.

[0029] When the dental coil is positioned as intended in the jaw region of the patient, the first element can be aligned substantially parallel to a frontal plane of the patient. It is also conceivable that when the dental coil is positioned as intended in the jaw region, the first element can be aligned substantially parallel to a dental arch of the patient, in particular parallel to a row of the patient's incisors. When the dental coil is positioned as intended in the jaw region, the first element can rest against a skin surface of the patient's jaw region or be at a predetermined distance of less than two centimeters, less than one centimeter, or less than five millimeters from the skin surface of the patient's jaw region.

[0030] The second element preferably has an antenna or a number of antennas held by the second element. The antenna or the number of antennas can, for example, be integrated and / or embedded in the second element and / or connected thereto. Preferably, the antenna or the number of antennas are reversibly deformable in order to be shaped to fit the jaw region of the patient. The second element can be designed as a wing or a flank which at least partially encloses a left cheek and / or a right cheek of the patient when the dental coil is positioned on the jaw region as required. The second element can, in particular, have a first flank and a second flank, wherein the first flank is shaped to fit the patient's left cheek and the second flank is shaped to fit the patient's right cheek. However, it is also conceivable for the second element to have only one flank.In this case, the dental coil can also have a third element, which, when positioned as intended, is arranged on the patient's cheek opposite the second element and is shaped to match the cheek. The third element can be designed analogously to an embodiment of the second element.

[0031] In a preferred embodiment, the dental coil according to the invention has a holder which is designed to hold and / or position the first element and / or the second element in a position according to application on the jaw region of the patient. In a simple example, the holder can have two struts or support elements which, when the dental coil is positioned according to application, flank or enclose the patient's head on a left side and a right side of the head. The holder can further have a holding element which is designed to carry out a fine adjustment of an orientation and / or a position of the first element and / or the second element relative to the jaw region of the patient.However, it is also conceivable for the holder to comprise a positioning unit configured to perform a rough positioning of the dental coil relative to the patient and / or a patient support device. A patient support device can be any structure that supports the patient in maintaining a predetermined position and / or posture during a magnetic resonance measurement. The patient support device can, in particular, be configured to support a body region of the patient in a sitting, lying, and / or standing posture.

[0032] By providing the first element with a recess, any impairment of the patient's breathing during a magnetic resonance measurement of the patient's jaw region is advantageously reduced or avoided. Furthermore, a contact surface of the dental coil on the skin surface of the patient's jaw region can be reduced to an area of the first element, which contributes to increased patient comfort and reduces the risk of the patient aborting the magnetic resonance measurement. Furthermore, manual positioning of the dental coil on the patient's jaw region can be simplified because the orientation and relative position of the dental coil to the patient's jaw region are already predetermined by the recess in the first element. This advantageously allows time to be saved when positioning the dental coil.

[0033] By providing the second element, which can be shaped to the patient's jaw region, one or more antennas of the dental coils can be advantageously positioned at a particularly close distance and / or individually adapted to the jaw region. This advantageously increases the signal-to-noise ratio of received magnetic resonance signals.

[0034] In one embodiment of the dental coil according to the invention, the second element can be positioned independently of the first element.

[0035] The dental coil according to the invention comprises a holder configured to hold the first element and / or the second element in the application-specific position on the patient's jaw region. The first element and the second element can, for example, be mechanically connected to different sections of the holder and / or the holding element, which are reversibly deformable independently of one another. It is also conceivable for the different sections of the holder and / or the holding element to be positionable and / or oriented relative to one another by means of an adjustment mechanism, such as a hinge, a joint, or a comparable mechanism.

[0036] Independent positioning of the first element and the second element can mean that the first element and the second element are separate from one another, in particular without a mechanical connection to one another. In this case, a position of the second element can be adjustable independently of a position of the first element. However, it can also mean that the second element is mechanically connected to the first element. In this case, in particular, a shape and / or a relative position of at least part of the second element relative to the first element can be adapted by means of the flexible element.

[0037] Independent positioning of the first and second elements can simplify adaptation of the dental coil to the individual geometry of a jaw region and / or reduce the distance between the jaw region and the dental coil. This advantageously increases the signal-to-noise ratio of the dental coil.

[0038] In an alternative embodiment of the dental coil according to the invention, the first element and the second element are mechanically connected to one another, wherein the second element is held by the first element.

[0039] It is conceivable that the first element and the second element are connected to one another by means of a hinge or a joint in order to improve the adaptation and / or shaping of the dental coil to the patient's jaw region. However, it is equally conceivable that the possibility of adapting and / or shaping the dental coil to the patient's jaw region is already provided by the flexible element. A mechanical connection between the first element and the second element can be realized by any desired material-fit, force-fit and / or form-fit connection. Of course, a third element can also be mechanically connected to the first element or be positionable independently of the first element.

[0040] By mechanically connecting the first element to the second element, the dental coil can be positioned particularly easily in the patient's jaw region. This advantageously reduces the time required for preparing magnetic resonance imaging of the jaw region.

[0041] In a further embodiment, the dental coil according to the invention further comprises an adjustment mechanism which is designed to adjust a shape of the flexible element in order to reshape the second element to the jaw region of the patient.

[0042] In one embodiment, the second element can be molded to the external shape of the patient's jaw region using the adjustment mechanism. For this purpose, the adjustment mechanism can comprise a guide mechanism, a tensioning mechanism, a clamping mechanism, a bending mechanism, a pulling mechanism, or the like, which is designed to deform the second element in the intended position on the patient's jaw region and / or to adjust a bending radius of the second element depending on a contour of the patient's jaw region. It is conceivable that the adjustment mechanism is mechanically connected to the holder of the dental coil.

[0043] The adjustment mechanism preferably has an adjusting element which is designed to transmit a force to the second element. An adjusting element can, for example, be a screw, a pin, a bolt and / or an elastic element which can be positionably mounted and / or clamped between the holder and the second element by means of the adjustment mechanism. A force exerted on the adjustment mechanism can be transferred to the second element by means of the adjusting element, such that the second element or a section of the second element is positioned relative to the jaw region of the patient. The adjustment mechanism can, in particular, have a plurality of adjusting elements which are designed to adapt a surface contour of a side of the second element facing the jaw region to a surface contour of the jaw region of the patient.The second element can come into contact with the skin surface of the patient's jaw region. However, it is also conceivable that a predetermined distance of less than two centimeters, less than one centimeter, or less than 5 millimeters is maintained between the second element and the skin surface of the patient's jaw region.

[0044] The actuating element can further comprise an elastic element, such as a synthetic or natural elastomer, a spring, a foam, or the like. When the dental coil is positioned in the jaw region as required for the application, the elastic element can be clamped between the second element and the positioning unit and / or the holder, and can transmit an elastic restoring force to the second element. Preferably, the second element is deflected in the direction of the patient's jaw region by means of the elastic restoring forces of the elastic element, thereby conforming to the patient's jaw region. However, the elastic element can also represent a holding element that holds at least the second element, but also the first element and / or the third element, in a position as required for the application in the patient's jaw region.

[0045] An advantage of the adaptation mechanism according to the invention is a particularly simple and / or time-efficient reduction of the distance between one or more antennas of the dental coil and the jaw region of the patient. This advantageously allows an increased signal-to-noise ratio of received magnetic resonance signals and / or a reduced preparation time for a magnetic resonance measurement of the jaw region of the patient to be achieved.

[0046] According to a further embodiment of the dental coil according to the invention, the flexible element comprises an intelligent material which is designed to change a material property depending on a predetermined excitation signal, wherein the adaptation mechanism is designed to support the adaptation of the shape of the second element by means of a transmission of the excitation signal to the flexible element.

[0047] A smart material can be any material in which a material property of the second element is changed in a predetermined manner by means of a suitable excitation signal. A material property can, in particular, relate to the deformability of the smart material. Further examples of affected material properties of the smart material include, among others, cohesive force, elasticity, stiffness, ductility, or strength. Preferably, a material property of the smart material can be adjusted by means of the excitation signal such that the second element is deformable compared to an unexcited reference state while applying a reduced amount of force.However, it is also conceivable that the smart material of the second element is flexibly deformable under manual force in the unexcited reference state, while the smart material exhibits reduced flexibility and / or deformability during and / or after application of the excitation signal (excited state). Furthermore, the smart material can also exhibit increased stiffness in the unexcited reference state, which is reduced during and / or after application of the excitation signal.

[0048] An excitation signal can comprise any electrical, thermal, and / or electromagnetic signal. The excitation signal can further comprise a mechanical vibration and / or a chemical reaction. In one example, the smart material comprises a shape memory polymer and / or a shape memory alloy, which assume a predetermined shape upon exceeding a predetermined temperature and / or upon irradiation with electromagnetic radiation of a predetermined wavelength (e.g., high-frequency signals from a magnetic resonance device, light of a predetermined spectrum, etc.). In another example, the smart material is configured to melt upon a slight temperature increase (thermal excitation signal), such as upon contact with the skin surface of the jaw region, and to enable improved conformation of the second element to the jaw region.It is also conceivable that the smart material could be deformed due to a piezoelectric effect or inverse piezoelectric effect when an electrical voltage and / or an electrical current is applied (see piezoelectrics). In addition, the second element can also comprise an electrorheological and / or magnetorheological fluid, an electrostrictive and / or magnetostrictive material, and / or a functional polymer. Micro- or nanoencapsulated materials and carbon nanotubes are also possible smart materials.

[0049] The use of intelligent materials advantageously reduces the effort required to reshape or mold the second element to the patient's jaw region, especially for multiple patients. This allows the antenna of the second element to be reproducibly and efficiently positioned at a short distance from the patient's jaw region, even with increased patient volume.

[0050] According to a further embodiment, the dental coil according to the invention further comprises a holder which is mechanically connected to the first element and / or the second element.

[0051] Preferably, the holder is mechanically connected to the first element and the second element. The holder can be designed according to an embodiment described above. The holder has, for example, two support elements that flank the patient's head on two sides when the dental coil is positioned as intended.

[0052] The first element and / or the second element can be positioned relative to the patient by means of the holder, wherein the holder is designed to hold the first element and / or the second element in the position according to use on the jaw region of the patient.

[0053] According to an embodiment described above, the holder can be positioned relative to the patient and / or the patient support device by means of the positioning unit. In one embodiment, the holder has a holding element that is mechanically connected to one or more support elements of the holder as well as to the first element and / or the second element. It is conceivable that the holder has a mechanism that is designed to adjust a position and / or an orientation of the holding element or the first element and / or the second element relative to the patient and / or the patient support device. According to an embodiment described above, the mechanism can be designed, for example, as a joint, a hinge, but also as a rotary bearing, a rolling bearing, a plain bearing, or the like.In particular, the holder provides the necessary mechanical stability to position and hold the first element and / or the second element in the jaw region of the patient as required.

[0054] Using the holder according to the invention, the dental coil can be positioned robustly and / or reproducibly on the patient's jaw region. This advantageously prevents relative movement between the dental coil and the patient during a magnetic resonance measurement of the jaw region. This can be particularly important when the first element and / or the second element are positioned at a short distance from the skin surface of the patient's jaw region, in order to avoid a reduction in patient comfort due to the dental coil resting on the skin surface.

[0055] According to a further embodiment, the dental coil according to the invention has a positioning unit which is designed to adjust a position and / or orientation of the holder relative to the patient and / or a patient support device.

[0056] The positioning unit is preferably designed as part of the holder. The positioning unit is configured to position the holder with the dental coil, in particular the first element and / or the second element, relative to the jaw region of the patient. The positioning unit can have any mechanism configured to adjust a position and / or an orientation of the dental coil, but also of the first element and / or the second element, relative to the patient. Adjusting a position and / or an orientation of the dental coil can, for example, comprise transporting the dental coil along at least one spatial direction and / or aligning the dental coil along at least one rotational axis. The positioning unit is preferably configured to move the dental coil along a plurality of spatial directions and / or rotational axes.The positioning unit may be mechanically connected to at least part of the holder.

[0057] In one embodiment, the positioning unit is designed to transport the dental coil relative to a patient support device. The positioning unit and / or the holder can have at least a first surface which is immovably mounted at a distance from a patient support surface of the patient support device. A uniform gap between the patient support device and the first surface can have a guide mechanism or be designed as such. The guide mechanism can, for example, have a roller system, a rail system, a linear guide, a telescopic system or the like. The positioning unit can in particular be designed to position the dental coil along a longitudinal axis of the patient support device by means of the guide mechanism. It is also conceivable for the positioning unit to have a second surface and / or a strip ora rod which is positioned at a predetermined distance from the first surface between the first surface and the patient support surface of the patient support device. A gap between the first surface and the second surface and / or the bar can in turn have a guide mechanism or be designed as such. The guide mechanism can be designed to limit movement of the holder relative to the patient support device to at least one predetermined spatial direction and / or movement trajectory. However, it is also conceivable for the guide mechanism to limit the movement of the holder relative to the patient support device to at least two or three predetermined spatial directions and / or movement trajectories.The first surface can be designed to accommodate the patient during a magnetic resonance measurement and / or to assist in maintaining a posture required for the magnetic resonance measurement.

[0058] In one embodiment, the positioning unit has a pivoting mechanism designed to pivot or tilt the holder relative to a longitudinal axis of the patient and / or the magnetic resonance device. For example, the first surface has a hinge or a joint designed to adjust an angle between the dental coil and the first surface and / or the patient support device. Preferably, the dental coil can be tilted relative to the first surface and / or the patient support device by means of the hinge or the joint. The hinge or the joint can further have a mechanism designed to lock the dental coil at a predetermined angle to the first surface.It is conceivable that locking the dental coil at the predetermined angle to the first surface is implemented by means of a latching mechanism, a guide mechanism, a plug-in mechanism, or a clamping mechanism. In addition, any other non-positive and / or positive locking mechanisms are of course conceivable. In a further embodiment, the positioning unit is pivotally mounted by means of the pivoting mechanism, wherein an angle of the positioning unit relative to a magnetic resonance device and / or a patient is adjustable.

[0059] By providing a positioning unit according to the invention, the position and / or orientation of the dental coil relative to the patient can be changed in a particularly time-efficient manner. Furthermore, blocking the patient's access to the patient support surface by a positionable dental coil can be advantageously avoided.

[0060] In a preferred embodiment of the dental coil according to the invention, the holder has a pivoting mechanism, wherein the first element and / or the second element are mounted by means of the pivoting mechanism so as to be pivotable relative to the patient through a maximum angle when the dental coil is positioned in accordance with the application on the jaw region of the patient, and wherein the maximum angle of the first element and / or the second element relative to the patient is selected such that a head of the patient can be positioned unhindered in a relative position to the holder according to the application.

[0061] The pivoting mechanism can, for example, comprise a hinge, a joint, a rotary bearing, a plain bearing, a rolling bearing, a roller bearing, and / or any other mechanism designed to pivot the first element and / or the second element at an angle relative to the holder and / or the patient support device. When the dental coil is positioned as intended, the first element and / or the second element are preferably pivotable along a sagittal plane of the patient. However, it is also conceivable for the first element and / or the second element to be pivotable approximately parallel to a frontal plane of the patient. When pivoting, the dental coil can follow a section of a circular arc determined by the pivoting mechanism. It is conceivable for the pivoting mechanism, according to an embodiment described above, to be comprised by the positioning unit and / or integrated therein.

[0062] In a preferred embodiment, the pivoting mechanism has a detent or resistance that indicates when a predetermined angle has been reached and / or prevents unwanted or uncontrolled pivoting. It is also conceivable for the pivoting mechanism to comprise an arrangement of cams or nipples that resist the pivoting movement of the first element and / or the second element and prevent the dental coil from being folded or unfolded in an uncontrolled manner.

[0063] Depending on the configuration of the magnetic resonance scanner and / or the patient support system, the maximum angle can be between 60° and 90°, 90° and 180°, or 180° and 270°. For magnetic resonance scanners where the patient assumes a standing or sitting position for the magnetic resonance examination, the maximum angle is preferably between 60° and 90°. However, larger maximum angle values are also conceivable. For conventional magnetic resonance scanners with a patient table, the maximum angle is preferably less than 180°.

[0064] By providing a pivoting mechanism, the first element and / or the second element can be positioned at a short distance from the patient's jaw region in a particularly time-efficient manner and then completely removed from the patient's access area to the patient support device. This advantageously compensates for the increased time required to position the dental coil in the jaw region as required for the application.

[0065] In the dental coil according to the invention, the holder has a guide mechanism with a guide axis, wherein the guide axis is aligned substantially parallel to an intersection line of a sagittal plane and a transverse plane at the jaw region of the patient, and wherein the guide mechanism is configured to position the first element along the guide axis in order to adjust a distance between the first element and the jaw region of the patient.

[0066] According to the invention, the guide axis is aligned substantially parallel to the intersection of a sagittal plane and a transverse plane in the patient's jaw region. However, it is also conceivable, although outside the scope of protection defined by the patent claims, that the guide axis is tilted by an angle, e.g., an angle between 0 and 15° or between 15 and 30°, relative to the transverse plane. In special cases, the guide axis can also be tilted by a few degrees relative to the sagittal plane.

[0067] The guide mechanism can comprise a guide element, such as a cylinder or a screw. For example, the screw can engage in a thread of the first element and / or the second element. Turning the screw can cause the screws to be screwed into the thread of the first element and / or the second element, which are thereby moved in the direction of the screw. For this purpose, the screw can be mounted in a predetermined position relative to the holder, so that movement of the screw in the direction of the first element and / or the second element is prevented during rotation. The holder can in particular comprise one or more pins or bolts which engage in complementary recesses or holes in the first element and / or the second element.The pins or bolts are preferably designed to provide guidance of the first element and / or the second element along an axis of the pins or bolts when the first element and / or the second element are positioned along the guide axis by means of the guide mechanism. The pins or bolts are preferably oriented parallel to the guide axis.

[0068] It is further conceivable that the first element and / or the second element are mechanically connected to a holding element. The screw of the guide mechanism can accordingly engage in a thread of the holding element in order to position the first element and / or the second element along the guide axis of the guide mechanism. The holding element can further have one or more recesses or holes that are designed to be complementary to the pins or bolts of the holder. The recesses or holes can, according to the example described above, provide a guide for the pins or bolts, which prevents twisting or tilting of the holding element in relation to the guide axis.

[0069] The guide axis can, in particular, represent a rotation axis of the screw of the guide mechanism. Preferably, the guide axis is aligned parallel to a sagittal plane, in particular a median or middle sagittal plane, of the patient.

[0070] By means of the guide mechanism according to the invention, a fine adjustment of the position of the first element and / or the second element in the jaw region of the patient can be carried out. This makes it possible to provide a particularly small distance between the skin surface of the jaw region and the first element and / or the second element, whereby the signal-to-noise ratio of the dental coil can be advantageously improved. It is also conceivable that the first element and the second element (but also the third element) can be positioned particularly evenly on the skin surface of the patient's jaw region along the guide axis by means of the guide mechanism. This makes it possible, in particular, to avoid twisting or tilting of the first element and / or the second element, which can lead to an uneven arrangement of antennas of the first element and the second element in the jaw region.

[0071] In one embodiment, the holder of the dental coil according to the invention has a gooseneck mechanism or an articulated hose.

[0072] A gooseneck mechanism may comprise a flexible, coiled tube that can be bent in any spatial direction and is designed to maintain a curved shape. For this purpose, the gooseneck mechanism may comprise a helical inner wire, which is wrapped by a wire with a substantially triangular cross-section.

[0073] For example, an articulated hose can be composed of ball-and-socket joints. The ball-and-socket joints can be clamped together and have a predetermined holding force that exceeds the weight of the first element and / or the second element. The articulated hose can be manually deformed or bent to position the first element and / or the second element (as well as the third element) and maintain a shape for the duration of a magnetic resonance measurement.

[0074] It is further conceivable that the gooseneck mechanism or the articulated hose has a locking mechanism designed to lock or secure the gooseneck mechanism or the articulated hose in a predetermined shape. It is further conceivable that the gooseneck mechanism or the articulated hose is mechanically connected to a holding element that supports the first element and / or the second element and / or holds them in a predetermined relative position.

[0075] By providing a gooseneck mechanism or an articulated tube, the first element and / or the second element can be positioned relative to the patient's jaw region in a particularly simple and time-efficient manner. Furthermore, a gooseneck mechanism and an articulated tube can represent a particularly cost-effective solution for positioning the dental coil and advantageously reduce the manufacturing effort of the dental coil. Furthermore, a gooseneck mechanism or an articulated tube offers increased openness of the dental coil. This can increase patient comfort and minimize the risk of aborting a magnetic resonance measurement.

[0076] According to a further embodiment of the dental coil according to the invention, the pivoting mechanism further comprises a damping element which is designed to dampen and / or limit a movement of the first element and / or the second element when pivoting the first element and / or the second element along a predetermined path.

[0077] In a preferred embodiment, the damping element is designed as a mechanical spring, a pneumatic element, such as a gas spring, or an elastic element. The damping element can be aligned along the predetermined path of the first element and / or the second element. For example, the spring can be positioned such that the further the first element and / or the second element are pivoted along the predetermined path toward the patient's jaw region, the more the movement of the first element and / or the second element is braked and / or damped.

[0078] However, it is also conceivable for the damping element, according to an embodiment described above, to have an arrangement of cams, locking elements, or nipples designed to resist movement of the first element and / or the second element along the predetermined path. The damping element can further be designed as a braking element that brakes or limits movement of the first element and / or the second element by means of a force-locking connection to the holder. Resistance that is resisted to movement of the first element and / or the second element along the predetermined path by means of the damping element can vary with the distance between the first element and / or the second element and the jaw region, and can increase toward the patient's jaw region.

[0079] By providing a damping element according to the invention, uncontrolled folding or pivoting of the dental coil can be advantageously prevented or limited. This can prevent patient injury due to improper positioning of the dental coil by an operator or the patient, particularly in magnetic resonance imaging devices where the patient is positioned vertically or standing.

[0080] In a further embodiment, the dental coil according to the invention further comprises a flexible holding element which, when the dental coil is positioned on the jaw region of the patient as intended, is connected at least to the second element, wherein the adjustment mechanism is designed as a pulling mechanism which is mechanically connected to the flexible holding element and is designed to provide a pulling force which guides the flexible holding element in a direction of the jaw region of the patient.

[0081] The first element and / or the second element can be connected to the flexible holding element and / or held by it. The first element and / or the second element can be connected to the flexible holding element in a force-fitting, form-fitting, and / or material-fitting manner. In a preferred embodiment, the flexible holding element can be positioned relative to a carrier element and / or a positioning unit of the holder and holds at least the second element in a position appropriate for the application in the jaw region of the patient. The pulling mechanism can, in particular, represent an adjustment mechanism according to an embodiment described above.

[0082] It is particularly conceivable that the flexible holding element is positioned between the patient's jaw region and the holder when the dental coil is positioned as intended. The flexible holding element can have a substantially cuboidal shape or a shape that is homeomorphic to a cuboid, which circumferentially encloses the jaw region from a left cheek region to a right cheek region of the patient. Preferably, a first end of the flexible holding element is mechanically connected to the left cheek region and a second end of the flexible holding element is mechanically connected to the right cheek region. The pulling mechanism can have a pulling element, such as a band, a rope, a net, a cord, or the like, which guides or deflects the first end and the second end in a direction away from the patient by means of the pulling mechanism.Such a direction can essentially point from a dorsal side of the patient in a direction away from the patient. The traction mechanism can comprise any mechanism designed to exert a tensile force on the traction element.

[0083] In one embodiment, the flexible holding element can be shaped to the patient's jaw region by means of the pulling mechanism. This can mean that the flexible holding element can be positioned along the patient's jaw region by means of the pulling mechanism. The flexible holding element can, for example, rest on the patient's skin surface and be shaped thereto by means of the pulling force. However, it is also conceivable for the flexible holding element to be spaced from the patient's skin surface by means of the first element and / or the second element. In this case, the flexible holding element can be designed to elastically deform at least the second element when a pulling force is exerted on the pulling element and to conform to the patient's jaw region.

[0084] In an alternative embodiment, the flexible holding element is designed to be positioned relative to the holder and clamped into the holder with elastic deformation. The flexible holding element can mold the second element to the jaw region of the patient independently of the adaptation mechanism. For example, elastic restoring forces of the flexible holding element can be selected such that the flexible holding element forms a force-fitting connection with the holder. It is particularly conceivable that the flexible holding element is positioned and / or clamped between the jaw region of the patient and the holder when positioned as required. The flexible holding element can be molded onto the jaw region of the patient. The elastic restoring force of the flexible holding element can in particular be tailored to a predetermined group of patients, such as, for example,The second element can be tailored to the specific patient (e.g., children, adolescents, adults, or seniors) so that the flexible holding element, when properly positioned on the patient's jaw region, exerts a predetermined pressure on the patient's jaw region and / or the second element. As described above, at least the second element can be positioned between the skin surface of the patient's jaw region and the flexible holding element and can be contoured to the patient's jaw region when the flexible holding element is positioned.

[0085] By providing a flexible holding element according to the invention, the second element can be advantageously shaped to the patient's jaw region in a particularly time-efficient manner.

[0086] In one embodiment, the local coil according to the invention further comprises a third element with a flexible element, wherein the flexible element is designed to enable a reshaping of the third element of the jaw region of the patient and wherein the third element is arranged on a side of the jaw region of the patient opposite the second element when the dental coil is positioned as intended, wherein the third element has an antenna which is designed to receive high-frequency signals in a frequency and power range of a magnetic resonance measurement.

[0087] The third element can be configured according to an embodiment described above. The third element can, in particular, be formed as part of the second element, be mechanically connected to the second element, or be separate from the second element. The third element shares the advantages of the second element. In particular, the reshaping of the jaw region using the dental coil can be further improved by using a separate third element.

[0088] In a further embodiment, the adjustment mechanism is configured to position the first element and the second element relative to each other.

[0089] For this purpose, the first element and / or the second element can be mechanically connected to separate support elements of the holder. The separate support elements can comprise a reversibly deformable material and / or an adjustment mechanism designed to position the second element relative to the first element. Similarly, the third element can be positioned relative to the second element by means of a separate support element of the holder.

[0090] However, it is also conceivable for the first element and the second element to be mechanically connected to a holding element of the mount, such as the flexible holding element. The holding element can comprise a plastically or elastically deformable material. Upon deformation of the holding element, the first element can be positioned accordingly relative to the second element.

[0091] By providing a holder which is designed to position the first element, the second element and / or the third element relative to one another, the antenna or the antennas of the dental coil can be advantageously shaped to an individual geometry of the jaw region of the patient.

[0092] According to one embodiment, the dental coil according to the invention has a fixing element which is designed to mechanically connect the holder and / or the first element to a head of the patient in order to fix the head of the patient in a predetermined relative position to the first element.

[0093] The fixation element can be designed, for example, as a loop-shaped cord, a band, or the like, which is mechanically connected to the holder and / or the first element and engages around a chin, a lower jaw, and / or the back of the patient's head. The cord or band can be designed, in particular, to fasten the first element and / or the holder to the patient's head and / or to brace it against the chin or lower jaw. In one embodiment, the fixation element can be connected to a pulling mechanism according to an embodiment described above, which is designed to apply a predetermined pulling force to the fixation element, so that the first element and / or the holder are pressed against the skin surface of the patient's jaw region with a force corresponding to the predetermined pulling force.

[0094] In a further embodiment, the fixation element can comprise an elastic material, such as an elastomer, in particular a rubber band or an elastic foam. For example, as described above, the fixation element can be elastically deformed when positioned between the holder and / or the first element and the jaw region of the patient, wherein elastic restoring forces of the fixation element fix the jaw region and / or the patient's head relative to the holder and / or the first element. In particular, the fixation element can be designed as an elastic foam. The elastic foam can also be clamped between the holder and the second element and press the second element onto the patient's skin surface, so that the patient's head is fixed in a predetermined position relative to the first element.

[0095] In a further embodiment, the fixation element is mechanically connected to the first element and can be positioned on the skin surface of the patient's jaw region by means of a suitable mechanism (e.g., the guide mechanism). The fixation element can in particular comprise an elastic material, such as a cushion filled with fluid (e.g., air, inert gas, or a liquid), a foam, an elastomer, or the like, which is positioned on a side of the first element facing the patient's jaw region. The fixation element can in particular be designed to distribute and / or cushion pressure on the skin surface of the patient's jaw region. Preferably, the first element can be positioned on the skin surface of the patient by means of a guide mechanism according to an embodiment described above.

[0096] In one embodiment, the fixation element is designed to be clamped between a forehead of the patient and the holder and to provide a force-fitting connection between the holder and the forehead of the patient.

[0097] By fixing the holder to the patient's forehead, a robust and reproducible positioning of the dental coil on the patient's jaw region can be advantageously provided.

[0098] By means of the fixation element according to the invention, the dental coil according to the invention can be advantageously positioned in a consistent or constant relative position to the jaw region of the patient.

[0099] In a further embodiment, the dental coil according to the invention further comprises a safety mechanism which is designed to move the dental coil into an opening position when the safety mechanism is actuated by a person in order to remove the dental coil from the position in which it is used on the jaw region of the patient.

[0100] The safety mechanism can, for example, be designed as a ripcord, which is configured to remove the dental coil, the holder, the first element and / or the second element from the application-specific position on the patient's jaw region when a predetermined tensile force is exerted. The ripcord is preferably mechanically connected to the first element and / or the second element. However, it is also conceivable for the ripcord to be mechanically connected to a securing element and / or the holding element, which connects the first element and / or the second element in a predetermined relative position to the holder. Releasing the securing element and / or the holding element by pulling on the ripcord can detach or release the first element and / or the second element from the holder.

[0101] However, it is also conceivable for the safety mechanism to comprise an electronic mechanism and an actuating element. The electronic mechanism can comprise a switch, a button, a camera and / or a microphone, which are designed to detect a switching command, a gesture and / or a voice message from the patient and / or the operator. The gesture and / or the voice message can in particular encode a command from the patient or operator to move the dental coil into the open position. The safety mechanism can further comprise a computing unit, a control unit and / or a logic unit, which, depending on the switching command, the gesture and / or the voice message, output a control signal for positioning the actuating element. The control signal can in particular be transmitted to a drive, which is designed to change a position of the actuating element.A suitable drive can be, in particular, an electric drive, but also a pneumatic, hydraulic, motor, or manual drive. Preferably, the actuating element is mechanically connected to the securing element and / or the holding element, which connects the first element and / or the second element to the holder in the predetermined relative position. In this way, the safety mechanism can release the first element and / or the second element from the holder depending on the switching command, the gesture, and / or the voice message, and move the dental coil into an open position.

[0102] By providing a safety mechanism according to the invention, the dental coil can be advantageously moved into an open position if the patient experiences discomfort and / or if a tolerable pressure on the skin surface of the jaw region is exceeded. This prevents accidents when positioning the dental coil according to the invention and advantageously increases the patient's sense of safety or confidence during a magnetic resonance measurement with the dental coil.

[0103] According to one embodiment, the dental coil according to the invention comprises a transmitting unit and a receiving unit, wherein the transmitting unit has at least one antenna configured to transmit high-frequency signals in a frequency and power range of a magnetic resonance device into a jaw region of a patient, and wherein the receiving unit has at least one antenna configured to receive magnetic resonance signals from the jaw region of the patient. It is conceivable that the at least one antenna of the transmitting unit coincides with the at least one antenna of the receiving unit.

[0104] By providing a dental coil with a transmitting unit, at least one antenna can be positioned in close proximity to the patient's jaw region. This advantageously limits excitation of the patient's tissue to the jaw region, thereby increasing the efficiency of the dental coil.

[0105] The magnetic resonance device according to the invention comprises a dental coil according to an embodiment described above, wherein the magnetic resonance device is designed to acquire high-frequency signals in a frequency and power range of a magnetic resonance measurement from a jaw region of a patient by means of the dental coil in order to perform an imaging of the jaw region of the patient.

[0106] The magnetic resonance device may comprise a mount according to an embodiment described above. The mount may be configured to hold and / or position at least one component of the dental coil, such as a first element, a second element, a third element, and / or a holding element, in a predetermined relative position to a jaw region of the patient. Furthermore, the mount may be mechanically connected to the magnetic resonance device, in particular to a patient support device and / or a patient table. However, it is equally conceivable for the mount to be a separate component from the magnetic resonance device. In this case, the mount may be mounted on a wall and / or ceiling of an examination room of the magnetic resonance device or reversibly attached to the patient table.The holder preferably has a positioning unit configured to adjust a position of the holder and / or the at least one component of the dental coil relative to the patient support device and / or the patient. It is also conceivable that the positioning unit is configured to adjust a spatial position and / or orientation of the at least one component of the dental coil and / or the holder.

[0107] Furthermore, the magnetic resonance device according to the invention has at least one electrical connection line designed to electrically connect an antenna of the dental coil to the magnetic resonance device. In one embodiment, the dental coil has one or more antennas designed as a transmitting unit. The transmitting unit can be connected to a radio-frequency unit of the magnetic resonance device by means of an electrical connection line. It is conceivable that the radio-frequency unit provides an alternating current, which is emitted as a radio-frequency signal from the transmitting unit into a volume of the patient's jaw region, thereby generating a B1 magnetic field. In a further embodiment, the dental coil has one or more antennas designed as a receiving unit.The receiving unit can be connected to a receiver channel of the magnetic resonance device via an electrical connection cable. The magnetic resonance device is thus capable of receiving magnetic resonance signals from the patient's jaw region and reconstructing magnetic resonance images based on the received magnetic resonance signals.

[0108] The magnetic resonance device according to the invention advantageously enables time-efficient and repeatable acquisition of magnetic resonance images of the patient's jaw region. Furthermore, the magnetic resonance device according to the invention shares the advantages of the dental coil according to the invention according to an embodiment described above.

[0109] Further advantages and details will become apparent from the following description of exemplary embodiments in conjunction with the drawings. They show the following schematic diagrams: Fig. 1 shows a schematic representation of an embodiment of a magnetic resonance device according to the invention, Fig. 2 shows a schematic representation of an embodiment of a dental coil according to the invention, Fig. 3 shows a possible embodiment of a dental coil according to the invention, Fig. 4 shows a possible embodiment of a dental coil according to the invention, Fig. 5 shows a possible embodiment of a dental coil according to the invention, Fig. 6 shows a possible embodiment of a dental coil according to the invention, Fig. 7 shows a possible embodiment of a dental coil according to the invention, Fig. 8 shows a schematic representation of an embodiment of a dental coil according to the invention, Fig. 9 shows a possible embodiment of a holder for a dental coil according to the invention. Fig. 10 shows a possible embodiment of a holder for a dental coil according to the invention, Fig. 11 shows a possible embodiment of a dental coil according to the invention.

[0110] In Fig. 1 A possible embodiment of a magnetic resonance device 10 according to the invention with a dental coil 26 according to the invention is schematically shown. The magnetic resonance device 10 comprises a magnet unit 11, which has, for example, a permanent magnet, an electromagnet, or a superconducting main magnet 12 for generating a strong and, in particular, homogeneous basic magnetic field 13 (B0 magnetic field). Furthermore, the magnetic resonance device 10 comprises a patient receiving area 14 for receiving a patient 15. In the present exemplary embodiment, the patient receiving area 14 is cylindrical and surrounded in a circumferential direction by the magnet unit 11. In principle, however, designs of the patient receiving area 14 that deviate from this example are also conceivable.

[0111] The patient 15 can be positioned in the patient receiving area 14 by means of a patient support device 16 of the magnetic resonance device 10. For this purpose, the patient support device 16 has a patient table 17 designed to be movable within the patient receiving area 14. The magnet unit 11 further has a gradient coil 18 for generating magnetic gradient fields, which are used for spatial encoding during a magnetic resonance measurement. The gradient coil 18 is controlled by a gradient control unit 19 of the magnetic resonance device 10. The magnet unit 11 can further comprise a radio-frequency antenna, which in the present exemplary embodiment is embodied as a body coil 20 permanently integrated into the magnetic resonance device 10. The body coil 20 is designed to excite atomic nuclei located in the basic magnetic field 13 generated by the main magnet 12.The body coil 20 is controlled by a radio-frequency unit 21 of the magnetic resonance device 10 and radiates radio-frequency signals into an examination room, which is essentially formed by a patient receiving area 14 of the magnetic resonance device 10. The body coil 20 can also be configured to receive magnetic resonance signals.

[0112] The magnetic resonance apparatus 10 has a control unit 22 for controlling the main magnet 12, the gradient control unit 19, and the radio-frequency unit 21. The control unit 22 is configured to control the execution of a sequence, such as an imaging gradient echo sequence, a TSE sequence, or a UTE sequence. Furthermore, the control unit 22 includes an evaluation unit 28 for evaluating digitized magnetic resonance signals acquired during the magnetic resonance measurement.

[0113] Furthermore, the magnetic resonance device 10 comprises a user interface 23, which has a signal connection to the control unit 22. Control information, such as imaging parameters and reconstructed magnetic resonance images, can be displayed to a user on a display unit 24, for example, on at least one monitor, of the user interface 23. Furthermore, the user interface 23 has an input unit 25, by means of which the user can enter parameters of a magnetic resonance imaging procedure.

[0114] Furthermore, the magnetic resonance device 10 has a dental coil 26, which is positioned on the jaw region 43 of a patient 15 (see Fig. 3 ) and transmits magnetic resonance signals from a volume of the jaw region 43 to the magnetic resonance device 10. The dental coil 26 preferably has an electrical connection line 27, which provides a signal connection to the radio-frequency unit 21 and the control unit 22. Just like the body coil 20, the dental coil 26 can also be designed to excite atomic nuclei and to receive magnetic resonance signals. To emit radio-frequency signals, a transmitting unit of the dental coil 26 is controlled by the radio-frequency unit 21. The dental coil 26 can enclose the head of the patient 15 on the outside along a longitudinal axis of the patient 15. The transmitting unit and / or a receiving unit of the dental coil 26 can be carried in particular by a holder 35 and / or a holding element 33, which are adapted to the external shape of the jaw region 43 of the patient 15 (see Fig. 3 ).

[0115] The illustrated magnetic resonance device 10 can, of course, comprise additional components that magnetic resonance devices typically have. It is also conceivable for the magnetic resonance device 10 to have a C-shaped, triangular, or asymmetrical structure of the magnetic field-generating components instead of the cylindrical structure. The magnetic resonance device 10 can, in particular, be a dedicated magnetic resonance device 10 configured to perform magnetic resonance imaging of the jaw region of a standing or sitting patient 15.

[0116] Fig. 2 shows an embodiment of the dental coil 26 according to the invention, in which the first element 30 and the second element 32 are positioned in the application-appropriate position on the jaw region 43 of the patient 15. In the present example, the first element 30 is mechanically connected to the second element 32, wherein the two wings or flanks 32a and 32b of the second element 32 are arranged at an angle to the first element 30. The right wing 32a is shaped to resemble the surface contour of a right cheek region of the patient 15, while the left wing 32b is shaped to resemble the surface contour of a left cheek region of the patient 15. A wing 32a or 32b of the second element 32 can also represent a third element. The first element 30 and / or the second element 32 can be positioned at a short distance from the skin surface of the jaw region 43 of the patient 15 or can rest against it.

[0117] As in Fig. 2 As shown, the first element 30 has at least one recess 31 designed to accommodate the nose and mouth of the patient 15. The first element 30 is made of a dimensionally stable or rigid material, which is preferably shaped to fit the mouth and / or nose region of the patient 15. In the example shown, the flexible element is made of an elastic material, in which an antenna of the second element 32 is embedded. The antenna preferably has flexible or bendable signal conductors so that the second element 32 can be shaped to fit the jaw region of the patient 15.

[0118] In Fig. 3 An embodiment of the dental coil 26 according to the invention is shown, in which an upper part of the holder 35a of the dental coil 26 is pivotally mounted relative to a lower part of the holder 35b and / or a positioning unit 44 of the dental coil 26. In the example shown, the dental coil 26 has a pivot mechanism 38, which in this case has a pivot bearing. The upper part of the holder 35a with the first element 30 can be pivoted or tilted relative to the patient support device 16 and / or the patient 15 about a pivot point, which is defined by a position of the pivot bearing. In the embodiment shown, the dental coil 26 further has a damping element 37, which limits or prevents an uncontrolled closing of the upper part of the holder 35a towards the patient 15.The damping element 37 provides a predetermined resistance to the locking elements 36i, which can be designed, for example, as cams, nipples, or bulges, when pivoting the upper part of the holder 35a. Furthermore, the upper part of the holder 35a has a locking element 36z, which stops the upper part of the holder 35a from moving toward the patient 15 and locks the upper part of the holder 35a in a predetermined position relative to the patient 15.

[0119] The positioning unit 44 is designed to position the dental coil 26 relative to the patient support surface of the patient support device 16 and / or the patient 15. The positioning unit 44 can be positioned along a suitable guide element 45, as shown. The positioning unit 44 is mechanically connected to a lower part of the holder 35b, which is connected to the upper part of the holder 35a by means of the pivot mechanism 38. The upper part of the holder 35a can also be considered a holding element 33 for the first element 30 and / or the second element 32.

[0120] The Fig. 3 The embodiment of the dental coil 26 according to the invention shown further comprises a guide mechanism 41 for fine adjustment of a position of the first element 30. When the dental coil 26 is positioned as intended on the jaw region 43 of the patient 15, for example, when the upper part of the holder 35a is in the closed state, a guide axis of the screw 41a is aligned substantially parallel to a line of intersection of a sagittal plane and a transverse plane on the jaw region 43 of the patient 15.

[0121] In Fig. 4 is an alternative view of the Fig. 3 shown embodiment of the dental coil 26 according to the invention. The guide mechanism 41 can, for example, have pins or bolts 41i that penetrate the upper part of the holder 35a and are mechanically connected to the first element 30. The guide mechanism 41 is designed to position the first element 30 along the Y-direction when the screw 41a is turned. The bolts or pins 41i of the guide mechanism 41 are guided through elongated holes in the upper part of the holder 35a and can be positioned relative to the patient 15 at least along the Z-direction by means of the screw plate 41b. The guide mechanism 41 can also be interpreted as a holding element 33, which is designed to hold the first element 30 in the application-appropriate position on the jaw region 43 of the patient 15 and / or to position the first element 30 relative to the jaw region 43 of the patient 15.

[0122] Fig. 5 shows an embodiment of the dental coil 26 according to the invention, in which the second element 32 is shaped by means of the flexible holding elements 46a and 46b to conform to the external shape of the jaw region 43 of the patient 15. The flexible holding elements 46a and 46b can, for example, consist of an elastic foam material that is matched to the expected geometry of the jaw region 43 of a patient group. Preferably, the flexible holding elements 46a and 46b are clamped or clamped between the holder 35 and the two wings 32a and 32b of the second element 32, so that the two wings 32a and 32b are held in a position appropriate for the application at a predetermined distance from the skin surface of the jaw region 43 of the patient 15.During the application-specific positioning of a flexible holding element 46, the flexible element of the second element 32 is preferably deformed such that a contour of one or more antennas of the second element 32 is shaped to match a contour of the jaw region 43 of the patient 15. The second element 32 is deformed and / or positioned relative to the first element 30 by means of the flexible holding element 46.

[0123] The first element 30 is as in Fig. 4 As shown, the second element 32 can be positioned on the skin surface or at a short distance from the skin surface of the jaw region 43 of the patient 15 by means of the adjustment mechanism 41. The flexible holding elements 46a and 46b can also be understood as a holding element 33, which contours the second element 32 to the jaw region of the patient and holds it in a position appropriate for use on the jaw region.

[0124] Fig. 6 shows an alternative embodiment of the dental coil according to the invention, in which the second element 32 is separate from the first element 30. The wings 32a and 32b of the second element 32 can be mechanically connected to a base of the holder 35 (e.g., a first surface) or the positioning unit 44. In this case, the flexible holding elements 46a, 46b of the Fig. 5 also function as fixation elements 50a, 50b and 50c, which fix the head of the patient 15 in a predetermined relative position to the first element 30 by pressing the two wings 32a and 32b of the second element 32 onto the skin surface of the patient 15.

[0125] In the present example, the first element 30 has a fixation element 50c made of an elastic material on a side facing the jaw region 43 of the patient 15. In this embodiment, the first element 30 is preferably brought into contact with the skin surface of the jaw region 43 of the patient 15 by means of the guide mechanism 41, so that the head of the patient 15 is fixed by the first element 30 in a predetermined position relative to the dental coil 26. The elastic material of the fixation element 50c can be designed to distribute the pressure of the guide mechanism 41 onto the jaw region 43 of the patient 15 and to increase the comfort of the patient 15 during a magnetic resonance measurement.

[0126] Fig. 7 shows an alternative embodiment of a dental coil 26 according to the invention with a fixation element 50. In the present example, the fixation element 50 comprises an elastic band that engages around the chin or lower jaw of the patient 15. The elastic band is preferably mechanically connected to the holder 35. Due to the elastic deflection of the elastic band when positioning the fixation element 50 on the chin or lower jaw of the patient 15, elastic restoring forces occur in the elastic band, which stabilize the patient's head or fix it in a predetermined position relative to the dental coil 26. It is also conceivable that the elastic band of the fixation element 50 is connected to a pulling mechanism (not shown) which is designed to press the elastic band against the head of the patient 15 with a greater force.

[0127] Fig. 8 shows an embodiment of the dental coil 26 according to the invention, in which at least the second element 32 is mechanically connected to a flexible holding element 46. The flexible holding element 46 is designed to mold the second element 32 to the jaw region of the patient 15 and to hold it in a position appropriate for performing a magnetic resonance measurement of the jaw region 43. In this case, the flexible holding element 46 comprises an elastic material with a substantially cuboid shape, which encloses the jaw region 43 of the patient 15 and molds the two wings 32a and 32b of the second element 32 to the jaw region 43. The dental coil 26 has a pulling mechanism 39, which is mechanically connected to a first end of the flexible holding element 46 on the left cheek region and a second end of the flexible holding element 46 on the right cheek region of the patient 15.The tensile force is provided by actuation, in particular rotation, of a central gear element 39a. The central gear element 39a is designed to rotate two gear rods 39b and 39c or to position them relative to one another, so that two tension rods 39d and 39e are rotated or moved relative to one another. The two tension rods 39d and 39e are further each connected to a spring roller 39f and 39g, which keep the tension elements 39h and 39i under tension and / or transmit a tensile force or a direction of the tensile force from the tension rods 39d and 39e to the holding element 33. The tensile force provided by the tension mechanism 39 is oriented such that the wings 32a and 32b of the second element 32 are pressed against the jaw region of the patient 15 by means of the flexible holding element 46.The first element 30 can be positioned on the flexible holding element 46 in accordance with the second element 32 or can be positioned separately therefrom on the jaw region 43 of the patient 15. It is particularly conceivable for the flexible holding element 46 to have a recess or an opening designed to receive the first element 30, so that the first element 30 can be positioned on the jaw region 43 of the patient independently of the flexible holding element 46.

[0128] Fig. 9 shows an embodiment of a holder 35 of the dental coil 26 according to the invention. The holder 35 in this case has two support elements 35a and 35b, which flank the head of the patient 15 (not shown) when the dental coil 26 is positioned as intended. The holder 35 further has a holding element 33, which is designed to hold the first element 30 (not shown) and / or the second element 32 (not shown) on the jaw region 43 of the patient 15. The holding element 33 has, in particular, an adjustment mechanism 41, which is designed to reshape at least the second element 32 (or a third element) to the jaw region 43 of the patient 15. In the example shown, the holding element 33 is particularly easy to detach from the holder 35 in order to allow access of the head of the patient 15 to a volume between the support elements 35a and 35b.

[0129] In the present example, the holding element 33 is connected to a safety mechanism 49, which is designed as a ripcord. The ripcord can be designed to release a mechanical connection between the holder 35 and the holding element 33 if a predetermined tensile force on the ripcord is exceeded. The holding element 33 can thus be released from the holder 35 in an emergency using the ripcord. The safety mechanism 49 can alternatively be designed as a button, a switch, or the like. The safety mechanism 49 can, in particular, be designed to control or actuate an actuating element that releases a mechanical connection between the holding element 33 and the holder 35. For this purpose, the safety mechanism 49 can also have a camera and / or a microphone, which are designed to record a gesture and / or a voice message from a person.The person's gesture and / or voice message can encode a request to move the dental coil 26 into an opening position.

[0130] Fig. 10 shows an embodiment of a carrier element 35a of the dental coil 26 according to the invention. In the example shown, the carrier element 35a has two fixation elements 50a and 50b, which are pivotally mounted on the carrier element 35a and can be fixed or secured in a predetermined position relative to the carrier element 35a. The fixation elements 50a and 50b have elastic cushions at ends pointing towards the patient 15, which, when the dental coil 26 is positioned as intended, are positioned laterally on the head of the patient 15 and / or the back of the head of the patient 15. The fixation elements 50a and 50b are designed in particular to support the patient's head during a magnetic resonance measurement or to limit or prevent movement of the head.

[0131] In Fig. 11An embodiment of the dental coil 26 according to the invention is shown, in which the first element 30 and the second element 32 are mechanically connected to a gooseneck mechanism 48. The gooseneck mechanism 48 can have a base plate 48a, which is connected to a holder 35 or a positioning unit 44. The first element 30 is mechanically connected to the second element 32 in this case. The second element 32 is deformable due to the flexible element and can be angled or bent relative to the first element 30 in order to enable reshaping of the jaw region 43 of the patient 15.

[0132] Although the invention has been illustrated and described in detail by the preferred embodiments, the invention is nevertheless 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 the invention.

Claims

1. Dental coil (26) comprising a retainer (35), a first element (30) and a second element (32), wherein the first element (30) consists of a dimensionally stable material and comprises a recess (31) which is suitable for receiving a mouth region and / or a nose region of a patient (15) when the dental coil (26) is positioned in a manner appropriate for use on a jaw region (43) of the patient (15), wherein the second element (32) has a flexible element which is designed to allow it to be shaped to conform to the contour of the jaw region (43) of the patient (15) by means of the flexible element, wherein the first element (30) and the second element (32) have an antenna which is embodied to receive radiofrequency signals in a frequency and power range of a magnetic resonance measurement, wherein the retainer (35) is mechanically connected to the first element (30) and / or the second element (32), wherein the first element (30) and / or the second element (32) can be positioned relative to the patient (15) by means of the retainer (35) and wherein the retainer (35) is embodied to hold the first element (30) and / or the second element (32) in the position appropriate for use on the jaw region (43) of the patient (15), characterised in that the retainer (35) has a guide mechanism (41) having a guide axis, wherein the guide axis is aligned substantially parallel to a line of intersection of a sagittal plane and a transverse plane on the jaw region (43) of the patient (15), wherein the guide mechanism (41) is embodied to position the first element (30) relative to the retainer (35) along the guide axis in order to set a distance between the first element (30) and the jaw region (43) of the patient (15).

2. Dental coil (26) according to claim 1, wherein the second element (32) can be positioned independently of the first element (30) or wherein the first element (30) and the second element (32) are mechanically connected to each other and wherein the second element (32) is held in place by the first element (30).

3. Dental coil (26) according to one of the preceding claims, further having an adjustment mechanism which is embodied to adjust a shape of the flexible element in order to shape the second element (32) to conform to the contour of the jaw region (43) of the patient (15).

4. Dental coil (26) according to claim 3, wherein the flexible element has a smart material which is embodied to modify a material property as a function of a predetermined excitation signal, wherein the adjustment mechanism is embodied to assist the matching of the shape of the second element (32) by means of a transmission of the excitation signal to the flexible element.

5. Dental coil (26) according to one of the preceding claims, further having a positioning unit (44) which is embodied to set a position and / or an orientation of the retainer (35) relative to the patient (15) and / or to a patient support and positioning device (16).

6. Dental coil (26) according to one of the preceding claims, wherein the retainer (35) has a pivoting mechanism (38) and wherein the first element (30) and / or the second element (32) are mounted so as to be pivotable by a maximum angle relative to the patient (15) by means of the pivoting mechanism (38) when the dental coil (26) is positioned in a manner appropriate for use on the jaw region (43) of the patient (15), wherein the maximum angle of the first element (30) and / or the second element (32) relative to the patient (15) is chosen such that a head of the patient (15) can be positioned unobstructed in a position appropriate for use relative to the retainer (35).

7. Dental coil (26) according to one of the preceding claims, wherein the retainer (35) has a swan-neck mechanism (48) or a joint hose.

8. Dental coil (26) according to claim 6, wherein the pivoting mechanism (38) further has a damping element (37) which is embodied to dampen and / or limit a movement of the first element (30) and / or the second element (32) when the first element and / or the second element (32) are / is pivoted along a predetermined path of travel.

9. Dental coil (26) according to claim 3, further comprising a flexible holding element (46) which is connected at least to the second element (32) when the dental coil (26) is positioned in a manner appropriate for use on the jaw region (43) of the patient (15), wherein the adjustment mechanism is designed as a pull mechanism (39) which is mechanically connected to the flexible holding element (46) and is configured to provide a tractive force which guides the flexible holding element (46) in a direction of the jaw region (43) of the patient (15).

10. Dental coil (26) according to one of the preceding claims, further having a third element with a flexible element, wherein the flexible element is embodied to allow the third element to be shaped to conform to the contour of the jaw region (43) of the patient (15) and wherein the third element is arranged on a side of the jaw region (43) of the patient (15) lying opposite the second element (32) when the dental coil (26) is positioned in a manner appropriate for use, wherein the third element has an antenna which is embodied to receive radiofrequency signals in a frequency and power range of a magnetic resonance measurement.

11. Dental coil (26) according to one of the preceding claims, further having a fixing element (50) which is embodied to mechanically connect the retainer (35) and / or the first element (30) to the head of the patient (15) in order to fix the head of the patient (15) in place in a predetermined position relative to the first element (30).

12. Dental coil (26) according to one of the preceding claims, further having a safety mechanism (49) which is configured to transfer the dental coil (26) into an open position when the safety mechanism (49) is actuated by a person in order to remove the dental coil (26) from the position appropriate for use on the jaw region (43) of the patient (15).

13. Magnetic resonance device (10) comprising a dental coil (26) according to one of the preceding claims, wherein the magnetic resonance device (10) is embodied to record radiofrequency signals in a frequency and power range of a magnetic resonance measurement from a jaw region (43) of a patient (15) by means of the dental coil (26) in order to perform an imaging scan of the jaw region (43) of the patient (15).