Head coil device with automatically positionable transmitting coil unit

Abstract

The invention relates to a head coil arrangement for a magnetic resonance tomograph, comprising a transmitting coil unit and a receiving coil unit, wherein the transmitting coil unit can be automatically positioned relative to the head coil arrangement in the longitudinal direction of the patient in a position of the head coil arrangement on the patient according to the application. Another aspect of the invention relates to a magnetic resonance system having a head coil arrangement, wherein the magnetic resonance system comprises a guide element which is designed to transmit a force to a driver, wherein the transmitting coil unit can be positioned by means of the force acting on the driver.

Description

Technical Field

[0001] The invention relates to a head coil arrangement for a magnetic resonance system, comprising a transmission coil unit and a reception coil unit, wherein the transmission coil unit can be automatically positioned relative to the head coil arrangement in the longitudinal direction of the patient in an application-dependent position of the head coil arrangement on a patient. Background Art

[0002] The head coil arrangement is used as a high-frequency transmission coil and reception coil in a magnetic resonance device. The individual coils can be integrated into the housing of the head coil arrangement or applied to the housing. It is also possible to mount the coil on a circuit board and to mount the circuit board on the housing via suitable fastening means, such as a plug connector.

[0003] If the coil is operated in receiving mode, the size of the coil relative to the size of the measurement object plays a decisive role in the resulting signal-to-noise ratio. The signal-to-noise ratio is optimal when the coil is positioned as close as possible to the surface of the measurement object, in this case the surface of the head. Large spacings of the individual coils from the measurement object result in a poor signal-to-noise ratio. Therefore, in a head coil, the entire head of the patient is usually tightly surrounded by the coil.

[0004] When developing new head coil arrangements with a greater number of individual coils, it is necessary to position the individual coils closer to the body region of interest, since the received signal strength is lower due to the smaller coils, resulting in a poorer signal-to-noise ratio at the same distance.

[0005] In particular, in magnetic resonance devices with ultra-high magnetic fields exceeding 7 Tesla, high-frequency transmission coils and reception coils are used, which provide optimal transmission efficiency for the corresponding body region. In order to fully utilize the advantages of the low signal-to-noise ratio of the device, the transmission coils and reception coils are not integrated into the patient tunnel as body coils, but are positioned as locally as possible on the body. In such devices, the patient tunnel is mainly a support tube for accommodating the patient.

[0006] In a head coil arrangement, the receiving coil unit can be designed so that there are small cutouts in the area of ​​the patient's nose and eyes. Thus, the patient can visually perceive part of his surroundings and, for example, can maintain eye contact with medical personnel.

[0007] In contrast, the possibility of cutouts in the transmission coil unit is very limited, since they have a negative effect on the field characteristics. Therefore, in current transmission coil units, the environment can only be perceived with the aid of a mirror in the head coil arrangement. If the transmission coil unit is positioned in a measuring position on the patient's head, direct eye contact with medical personnel or relatives is interrupted and the visual perception of the surroundings is severely limited. In a clinical environment, this situation can be a major obstacle, especially for claustrophobic patients or children, and can lead to premature termination of the examination. Summary of the invention

[0008] The object underlying the present invention is therefore to provide a head coil arrangement which improves the possibility of visual contact between the patient and medical personnel or relatives.

[0009] This object is achieved by a head coil arrangement and a magnetic resonance apparatus according to the invention.

[0010] The head coil device according to the present invention comprises a transmitting coil unit and a receiving coil unit, wherein the transmitting coil unit can be automatically positioned relative to the head coil device in the longitudinal direction of the patient in the position of the head coil device on the patient according to the application. Here, the position of the head coil device according to the application is preferably the head area of ​​the patient. In order to perform a magnetic resonance examination, the patient is usually moved into the patient tunnel of the magnetic resonance device in a lying position on the examination bed. The head coil device is usually fastened to the examination bed in a predetermined position to avoid relative movement between the examination bed and the head coil device during the examination. In order to accommodate the head, the receiving coil unit and the transmitting coil unit can be movably supported at the head coil device. It is conceivable that the receiving coil unit and the transmitting coil unit can be positioned independently of each other relative to the head coil device. Here, the transmitting coil unit can be positioned automatically in particular. This can mean that the transmitting coil unit is not only actively moved by means of a drive device or passively moved to a preset measurement position by means of a movement of a component of the magnetic resonance device. Here, the drive device can include a transmission device and / or a motor. In order to control the drive device, a corresponding interface or control element is preferably provided, which can be controlled, for example, by means of a control instruction or a control logic to actively position the transmitting coil unit. A feasibility for passive positioning is, for example, to utilize the movement of an examination bed, which can be moved into the patient tunnel at the beginning of the magnetic resonance examination and moved out again after the examination is completed. Preferably, once the patient moves into the patient tunnel by means of the examination bed, the automatic positioning of the transmitting coil unit is started. It is also more advantageous to start the automatic positioning of the transmitting coil unit as the head enters the patient tunnel. It is particularly desirable that the automatic positioning of the transmitting coil unit is started when the patient loses visual contact with the medical staff due to being transported into the patient tunnel. For example, the loss of visual contact can be determined based on the position of the head coil device on the examination bed, the position of the examination bed relative to the patient tunnel and the diameter of the patient tunnel. It is also conceivable that the automatic positioning of the transmitting coil unit is started after the patient's visual range is completely limited by the patient tunnel.

[0011] The receiving coil unit and the transmitting coil unit can usually be positioned independently of each other and can have the same initial position and measurement position. For this reason, the housings of the receiving coil unit and the transmitting coil unit are preferably constructed to complement each other. This can mean that the housings of the receiving coil unit and the transmitting coil unit can be positioned, engaged in each other, movable into each other and / or locked into each other, for example, in an overlapping manner. Because the receiving coil unit can have cutouts for the nose and eyes, the patient's field of vision is usually only slightly limited by the receiving coil unit. Therefore, the receiving coil unit can be positioned in a preset measurement position above the patient's head before the magnetic resonance examination. Because the patient's head has been fixed by the receiving coil, the transmitting coil unit can be moved to the preset measurement position without danger and automatically.

[0012] By automatically moving the transmitting coil unit to the preset measuring position, the duration during which the patient's field of vision is limited by the transmitting coil unit can be advantageously reduced. In addition, the patient can always maintain visual contact with the medical staff until the visual contact is interrupted by the patient tunnel.

[0013] Other advantageous embodiments are described herein.

[0014] According to another embodiment, the head coil device has a linear guide device, by means of which the transmission coil unit can be freely positioned on a defined movement path. This means that the transmission coil unit can be moved to a predetermined position along a known trajectory. The movement path is preferably defined by a linear guide device, which can be configured as a linear structure of any length, such as a rod, a screw, a track, a T-shaped profile, a groove, etc. Here, all structures whose extension is decisively directed to a certain direction can be regarded as linear. Therefore, such a structure can also have a curved movement path. The transmission coil unit can have a corresponding counterpart for the linear guide device, such as an eyelet, a slide, a retaining member or a C-shaped profile. The transmission coil unit can move along the linear guide device by means of a corresponding counterpart, wherein the direction of the longitudinal extension of the linear guide device is preferably consistent with the longitudinal direction of the patient. It is conceivable that the linear structure of the linear guide device is connected to the head coil device in an immovable manner. It is also conceivable that the linear structure of the linear guide device is installed at the transmission coil unit. In this case, the corresponding counterpart can be connected to the head coil device.

[0015] By using the linear guide, the transmission coil unit can be guided along a straight path with high precision. As a result, the gap between the housing of the reception coil unit and the housing of the transmission coil unit and the spacing of the coil from the patient can be reduced in an advantageous manner.

[0016] In another embodiment of the head coil device according to the present invention, the transmitting coil unit is pivotably supported at the head coil device at a maximum angle relative to the head coil device, wherein the maximum angle between the transmitting coil unit and the head coil device is selected so that the patient's head can be positioned in the head coil device without hindrance. The transmitting coil device can be pivotably supported at the head coil device, for example, via a hinge, a hinge or other suitable type of bearing. The bearing can be fastened to the head coil device and / or the transmitting coil unit. Pivotable can especially mean that the angle between the head coil device and the transmitting coil unit can be reversibly changed. Here, the angle preferably relates to the head coil device and the transmitting coil unit arranged in parallel on the examination bed, which are lifted from the surface of the examination bed along an arc and move in the direction of the patient tunnel. The maximum angle between the head coil device and the transmitting coil unit can be selected so that the head can be positioned in the head coil device without hindrance. The angle can be greater than 60°, for example. The angle is preferably greater than 90°. The angle is particularly preferably between 135° and 180°. It is also conceivable that the transmitting coil unit has an angle of 180° relative to the head coil device in the initial position. As the examination begins, before the patient is moved into the patient tunnel, the transmission coil unit can be pivoted to another angle, preferably 90° or less. Thus, once the transmission coil unit is moved on the examination bed into the patient tunnel, the highest position of the transmission coil unit has been exceeded and a collision between the two can be ruled out.

[0017] The pivotably mounted transmission coil arrangement provides a particularly easy-to-operate and robust guidance of the transmission coil unit relative to the head coil arrangement.

[0018] In another embodiment, the head coil device has a drive device for moving the transmission coil unit, which applies a force to the transmission coil unit so that the transmission coil unit moves along the movement path. Here, the drive device can include a device that provides any energy form, which is converted into kinetic energy in the transmission coil unit. Possible energy forms are, for example, internal energy, mechanical energy, electrical energy and radiation energy. The drive device is preferably connected to the head coil device and the transmission coil unit. It is also conceivable that, in addition to one or two of the components mentioned, the drive device is also connected to the magnetic resonance tomography scanner, the examination bed and / or the receiving coil unit. The drive device can have a transmission device, which, for example, converts force, torque or motion and transmits it to the transmission coil unit. As a result, the energy provided can be used to move the transmission coil unit in a defined manner. The drive device is preferably made of a material compatible with the magnetic field and electromagnetic excitation of the magnetic resonance tomography scanner. It is also conceivable that incompatible components of the drive device are arranged outside the patient tunnel and transmit force or energy to the conversion device, which converts force or energy into motion at the transmission coil unit. The drive device may have an interface and / or a control element via which the drive device is actuated. The interface may be connected, for example, to a control logic, a magnetic resonance tomograph or a control device of the magnetic resonance tomograph.

[0019] By using a drive device for moving the transmission coil unit, the transmission coil unit can be advantageously actuated as required and positioned in difficult-to-reach locations in the patient tunnel.

[0020] According to a relevant embodiment of the head coil device according to the present invention, the drive device for moving the transmission coil unit is a hydraulic or pneumatic drive device. The hydraulic drive device preferably has a liquid or a mixture of liquids, which can transmit force to the transmission coil unit due to internal energy, potential energy and / or kinetic energy. The transmission of force can be achieved by means of a corresponding working element, such as a piston or a cylinder, but can also be achieved using a hydraulic motor. The working element is usually connected to a pipeline system, which transports a hydraulic fluid and is mechanically coupled to the working element. The working element can be directly or indirectly connected to the transmission coil unit. By correspondingly adjusting the area ratio and volume ratio of the working element and / or the hydraulic pipeline, any force and movement can be transmitted to the transmission coil unit. In contrast, the pneumatic fluid has a gas or a mixture of gases. The force transmission can be achieved similarly to the hydraulic drive device by means of a corresponding working element suitable for pneumatic use. The drive device for the hydraulic or pneumatic working device is preferably positioned outside the examination room of the magnetic resonance tomography scanner. In this case, the force transmission can be realized via a pipeline system, which is connected to the transmission coil unit in the examination room via the working element. However, it is also conceivable that the drive device of the hydraulic or pneumatic working device is positioned in the examination room or connected to the magnetic resonance device, for example to the examination bed or the head coil device. The drive device can be, for example, a pump, a compressor or any drive element with a rotary, linear or vibrating drive principle.

[0021] The pneumatic and hydraulic working media and the corresponding line systems can be selected such that a low interaction with the magnetic field and / or electromagnetic signals of the magnetic resonance device occurs. This makes it possible to provide a cost-effective and magnetic resonance-compatible drive system.

[0022] In another feasible embodiment, the drive device for moving the transmitting coil unit has a motor. This can be any motor that converts heat energy, electrical energy or internal energy into mechanical work. The motor can be an AC motor, a DC motor, a linear motor, a piezoelectric motor, a stepper motor or a servomotor in particular. It is conceivable that, according to the above example, the motor drives a pneumatic or hydraulic working medium. However, the motor can drive a mechanical transmission element, such as a belt drive or a connecting rod drive, or can be mechanically coupled to the transmitting coil unit via a transmission. If the motor is coupled to the transmitting coil unit via a mechanical transmission element, the motor can be positioned outside the magnetic field of the magnetic resonance device and made of a common material for the motor. On the contrary, if the motor is positioned in the magnetic field of the magnetic resonance device, the motor preferably has a non-magnetic material and a small conductive structure. A feasible example of a suitable motor for working without a magnetic field is a piezoelectric motor.

[0023] By using a motor, a defined force or movement can be generated, which is transmitted to the transmission coil unit. As a result, complex transmission elements for transmitting force and movement can be avoided as much as possible. This simplifies the system design and advantageously increases the ability of the drive component to be integrated into the magnetic resonance device.

[0024] In one embodiment, the head coil device and / or the transmitting coil unit has a mechanical damping element, which is configured to receive the transmitting coil unit in a vibration-damping manner at a stop position of the movement path. The mechanical damping element can, for example, have a spring, an air cushion and / or an elastic or friction element to avoid sudden braking of the transmitting coil unit when the end point of the movement path is reached. The mechanical damping element can be fastened to the head coil unit or the transmitting coil unit. The mechanical damping element is preferably positioned at the stop point at the end of the movement path of the transmitting coil unit. It is also conceivable that the mechanical damping element consists of a plurality of elements joined to each other, at least one of which is connected to the transmitting coil unit and at least one of which is connected to the head coil device. Such a mechanical damping element can, for example, have a buffer or a gas pressure spring.

[0025] By using a mechanical damping element, the movement of the transmission coil unit is advantageously braked in a vibration-damping manner at the end of the movement path. As a result, noises and collisions in the head coil arrangement that could disturb and / or irritate the patient can be avoided.

[0026] In a preferred embodiment of the head coil device according to the present invention, the transmission coil unit has a driver, wherein the driver is configured to transmit force when in mechanical contact with the guide element of the magnetic resonance device, wherein the transmission coil unit can be positioned by means of force transmission. The driver can include any three-dimensional body protruding from the surface of the transmission coil unit, such as a cube, a cylinder, a pyramid or their homeomorphs. The driver is preferably fastened to the surface of the housing of the transmission coil unit. For this purpose, it is conceivable that the driver is bonded, welded, screwed or otherwise connected to the surface of the housing. Here, it is also conceivable to have a releasable form of connection, wherein the housing of the driver and the transmission coil unit are, for example, engaged in each other and / or connected to each other via a locking element. It is also conceivable that the driver is movably supported at the housing of the transmission coil unit. For this purpose, the driver and / or the housing of the transmission coil unit can, for example, have a hinge, a bearing or a spring. The shape of the driver is designed so that force transmission can be achieved by means of a guide element. Similar to the driver, the guide element can be any three-dimensional body protruding from the surface of the magnetic resonance device. The guide element can be connected to the surface of the magnetic resonance device in a similar manner to the driving member. The surface of the magnetic resonance device can include, for example, the surface of the examination bed, the outside or inside of the patient tunnel, or the surface of the housing component of the magnetic resonance device. The guide element is preferably positioned on the inner side of the patient tunnel so as to achieve force transmission by means of the driving member. The guide element is particularly positioned on the inner side of the patient tunnel so that once the driving member moves into the patient tunnel together with the transmitting coil unit on the examination bed, the guide element contacts the driving member at a defined point. The point is preferably selected so that when the driving member contacts the guide element, the patient's field of vision has been limited by the patient tunnel. Because the transmitting coil unit is movably supported on the head coil device, the force transmission between the driving member and the guide element causes the transmission coil unit to move relative to the head coil device and / or the examination bed. In other words, during the further movement of the examination bed into the patient tunnel, the transmitting coil unit can be stopped by the contact of the driving member with the guide element. The driving member and the guide element preferably have non-magnetic, non-conductive materials.

[0027] By means of the force transmission between the driver and the guide element, the transmission coil unit can be automatically moved into the measuring position due to the movement of the examination table, thereby avoiding further active components and making the head coil device more cost-effective to manufacture.

[0028] In another possible embodiment, the driver is connected to the drive device and is designed to transmit the movement to the transmission coil unit. In the embodiment, according to one of the above-mentioned embodiments, the driver can be connected not only to the transmission coil unit but also to the drive device. As a result, the movement or force of the drive device can be transmitted to the transmission coil unit via the driver, and the position of the transmission coil unit relative to the head coil device can be changed. It is also conceivable that in the embodiment, the driver is implemented as a part of the drive device.

[0029] In this embodiment, a part of the drive device can be advantageously positioned outside the magnetic field of the magnetic resonance system and mechanically connected to the driver of the transmission coil unit. The part of the drive device positioned outside the magnetic field can be manufactured more cost-effectively because the interaction with the magnetic field is negligible.

[0030] In another embodiment, the driving member is configured to change the value of the force acting on the guide element along the movement direction of the transmission coil unit according to the position of the transmission coil unit. It is conceivable that the driving member is made of an elastic material, such as an elastomer composed of natural rubber or silicone rubber, but also made of plastic, such as polyethylene or polyvinyl chloride, and deforms when the force is transmitted by means of the guide element. Here, although the driving member can be elastically deformed by the force transmission by means of the guide element, the positioning of the transmission coil unit in the measurement position is still achieved. In addition, when a limited force is exceeded, for example, when the transmission coil unit is in a stop position or a measurement position, the driving member can be deformed so that the guide element can pass by the driving member. Here, the transmission coil unit can be locked in the measurement position or closed with the head coil device in a shape-fitting manner in the measurement position. Through the elastic driving member, the transmission coil unit can be positioned in the measurement position before the movement of the examination bed ends. In this case, the elastic driving member passes by the guide element under the condition of reversible elastic deformation.

[0031] The change of force transmission between the driver and the guide element can also be understood as that the driver has a geometry that opposes the guide element with a variable resistance when guiding relative to each other in the forward motion direction. This can be achieved, for example, by a wedge-shaped or triangular cross section of the driver, which points to the direction of the guide element with a tip and hinders the guide element at a defined angle on the linear motion trajectory on the side. When the guide element is guided along the angled side of the driver, in addition to the force component pointing to the motion direction of the transmission coil unit, at least one other force component pointing to the angled side of the driver can also appear. The force pointing to the angled side of the driver can move the driver, for example, out of the guide device or the support, so that the driver moves away from the motion trajectory of the guide element, and the driver and the guide element can pass each other in the motion direction. Here, the driver can, for example, be supported by a spring, a flip mechanism or an elastic or movable element that opposes the guide element with a defined resistance. Preferably, the resistance is measured so that before the driver moves away from the motion trajectory of the guide element, the transmission coil unit moves to the measuring position when passing the guide element.

[0032] In this embodiment, the guide element and the driver can pass each other during a defined force transmission. As a result, the transmission coil unit can pass by the guide element in the measuring position, so that the patient on the examination bed can be moved further into the patient tunnel. This can be advantageous if, in addition to the patient's head, lower body regions, such as the shoulders or chest region, are to be examined. As a result, automatic positioning of the transmission coil unit can be achieved particularly simply and cost-effectively.

[0033] In a related embodiment, the driver is configured to change the direction of the force acting on the guide element according to the position of the transmitting coil unit. As described above, the change in the direction-related force transmission between the driver and the guide element can be realized, for example, by a wedge-shaped or triangular cross section of the driver. In the first direction of motion, the guide element can be guided along the angled side of the driver, wherein the force transmission between the driver and the guide element is related to the position of the transmitting coil unit. In the second direction of motion, the driver can, for example, hinder the guide element by means of a side parallel to the orientation of the guide element, so that the two cannot pass each other or can pass under the condition of applying a greater force. Here, it is particularly conceivable that the driver and / or the guide element have an elastic material, which is deformed when a limited force acts, so that the driver and the guide element can pass each other. It is also conceivable that the first driver is mechanically coupled to the second driver, so that once the first driver moves away from the motion trajectory of the guide element, the second driver moves from any position to the motion trajectory of the guide element. The mechanical coupling of the first and second driving members can be realized, for example, via a pin or a lever, which disengages the locking of the first hinge of the first driving member when it is moved, and simultaneously moves the second driving member to the desired position and locks the second hinge thereat. Conversely, in the opposite direction of movement, while the first driving member is erected and the first hinge is locked, the pin can disengage the locking of the second hinge of the second driving member. Preferably, the mechanical coupling between the two driving members is configured so that when the first driving member contacts the guide element, the first driving member moves the transmitting coil device to the measuring position when it moves into the patient tunnel and then flips over due to the force of the guide element. Thus, a second driving member can be set up, and when the examination bed is moved out of the patient tunnel, the second driving member moves the transmitting coil unit back to the initial position when it contacts the guide element.

[0034] The described embodiments make it possible to automate the movement of the transmission coil unit in an advantageous manner by means of simple mechanical components, thereby avoiding undesired influencing of the imaging of the magnetic resonance system by active motor components and / or drive components.

[0035] According to another embodiment, the transmitting coil unit and the receiving coil unit are connected to each other in a predetermined position and can be positioned relative to the head coil device. The connection can be implemented as a bolt connection, adhesive bonding, form fit, a locking mechanism or any releasable or non-releasable fastening system, for example. By connecting, the relative movement between the transmitting coil unit and the receiving coil unit is particularly avoided. In the above-mentioned embodiment, once the driving member at the transmitting coil unit abuts against the guide element and the movement of the examination bed in the direction of the patient tunnel continues, the transmitting coil unit is moved to the measuring position. By connecting the transmitting coil unit and the receiving coil unit, the receiving coil unit is also moved to the measuring position. For this purpose, the transmitting coil unit and the receiving coil unit are preferably movably supported on the head coil device. It is conceivable that the patient's head is supported in an open support and / or a shaped pillow that is connected to the head coil device and does not limit the patient's field of vision. The support can fix the patient's head in the correct position so that the transmitting coil unit and the receiving coil unit can be safely and automatically moved to the measuring position.

[0036] The connection of the transmitting coil unit and the receiving coil unit advantageously avoids limiting the patient's field of vision before entering the patient tunnel, thereby reducing the rate of premature termination of the magnetic resonance examination, in particular in the case of claustrophobic patients.

[0037] The magnetic resonance device with head coil device according to the present invention comprises a guide element, which is configured to transmit force to the driving member, wherein the transmission coil unit can be positioned by means of the force acting on the driving member. The guide element can be connected to the surface of the magnetic resonance device. The guide element is preferably positioned at the surface of the examination bed and / or the inner surface of the patient tunnel. In a feasible embodiment, the position of the first guide element is selected so that when the driving member moves into the patient tunnel together with the transmission coil unit on the examination bed, the first guide element contacts the driving member at a defined point. Through the force transmission between the driving member and the first guide element, the transmission coil unit can automatically move to the measurement position. On the contrary, the position of the second guide element is selected so that when the driving member moves out of the patient tunnel together with the transmission coil unit on the examination bed, the second guide element contacts the driving member at a defined point. Thus, the transmission coil unit can automatically move to the initial position. The defined contact points between the first driving member and the guide element and between the second driving member and the guide element are preferably selected so as to avoid limiting the patient's visual range outside the patient tunnel. It is conceivable that the magnetic resonance device has a plurality of guide elements, wherein one or more guide elements interact with one or more driving members during the movement of the examination bed in the direction of the patient tunnel. It is also conceivable that one or more guide elements interact with one or more driving members during the movement of the examination bed in the direction opposite to the patient tunnel. In addition, one or more guide elements can also be connected to the drive device and transmit the movement to one or more driving members or directly to the transmission coil unit.

[0038] By using the guide element, the transmitting coil unit can be positioned precisely along the movement path in an advantageous manner.

[0039] According to another embodiment, the guiding element is configured to change the direction of the force acting on the driving member and / or the value of the force acting on the driving member in the direction of movement of the transmitting coil unit according to the position of the transmitting coil unit. To this end, as described above, the guiding element can have an elastic material and / or a corresponding geometric shape and / or can be movably, elastically or elastically supported. In the embodiment, the variable value and / or direction of the force can act on the guiding element and cause the guiding element to deform, flip and / or trigger a mechanism acting on the second guiding element. The guiding element can be moved away from the movement trajectory of the driving member and / or cause a change in the position of the second guiding element by force transmission by means of the driving member. In the embodiment, the driving member of the transmitting coil unit is preferably implemented as a rigid element.

[0040] In this embodiment of the guide element, the movement of the examination table can be advantageously utilized for automatic positioning of the transmission coil unit, thereby avoiding the costs for active motor and drive components.

[0041] In another embodiment, the magnetic resonance device according to the invention comprises an examination bed, wherein the examination bed has a guide element, which is configured as a driver for transmitting a force to the transmission coil unit. It is conceivable that the guide element is positioned on a non-movable part of the examination bed and / or interacts with the driver of the transmission coil unit via one of the above-mentioned possibilities. In this case, the guide element is particularly configured to move the transmission coil unit from a measuring position to an initial position when the driver contacts the guide element and the examination bed moves in a direction opposite to the patient tunnel. In the simplest case, the guide element can be implemented as a sleeve, a pin or a bolt.

[0042] By means of the guide elements on the examination bed, the transmission coil unit can be automatically moved into the starting position by means of the movement of the examination bed. In this embodiment, the structural complexity of the automatic movement of the transmission coil unit can be reduced in an advantageous manner.

[0043] According to another embodiment, the magnetic resonance device includes a drive device, which is connected to the guide element and applies a force to the carrier of the transmission coil unit. The drive device is preferably designed to move the guide element along a defined motion path. Such a motion path can be derived, for example, from a linear guide, a pivot bearing, a screw drive, etc. However, the drive device can also be a hydraulic or pneumatic drive device that transmits force and / or motion to the guide element via a corresponding working element. In particular, it is conceivable that the drive device for the guide element is coupled to the drive device of the examination bed in order to achieve the movement of the guide element. However, the guide element can also be connected to the drive device of the examination bed via a coupling device or have an independent drive device, which may be driven by a dedicated motor according to one of the above examples.

[0044] In this embodiment, the transmission coil unit can be positioned independently of the movement of the examination table. As a result, the time period for the movement of the transmission coil unit can be adapted to the patient in an individual manner.

[0045] In another embodiment of the magnetic resonance device according to the present invention, the drive device of the guide element is connected to the motor. Here, the force and / or movement of the motor is preferably transmitted to the guide element via the drive device so that the transmission coil unit moves along a defined movement path. The drive device can be configured to change the force, movement direction or deflection of the guide element. All variants and combinations of mechanical, pneumatic, hydraulic and electrical drive devices can be conceived here. The drive device is preferably coupled to the motor of the examination bed so that the movement of the motor is transmitted to the guide element by means of the drive device. Here, the movement of the guide element can be decoupled from the movement of the examination bed by means of a coupling device. It is also conceivable that the guide element has an independent motor. The independent motor is preferably connected to the examination bed or positioned near the magnetic resonance device. A feasible embodiment is a linear motor, which is positioned outside the patient tunnel and transmits the translational movement to the guide element via an extension. The extension can be, for example, a non-magnetic, non-conductive plastic rod that provides a drive device for the guide element. In addition, it is also conceivable to have a non-magnetic component and a motor that can be positioned not only in the patient tunnel but also outside the patient tunnel. The motor can in particular have an interface by means of which the motor can be actuated via control commands. The control commands can be triggered by a person, for example a doctor or a patient, via an input on a control console or a remote control device. It is also conceivable that the control commands for actuating the motor are generated directly by the magnetic resonance system in order to coordinate the movement of the guide element with the imaging sequence.

[0046] By using a motor, the transmission coil unit can advantageously be positioned independently of the movement of the examination table and coordinated with the patient. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Further advantages and details emerge from the following description of an exemplary embodiment in conjunction with the accompanying drawings. In the schematic diagram:

[0048] Figure 1 A magnetic resonance system having a head coil arrangement according to the invention is shown.

[0049] Figure 2 A possible embodiment of the head coil device according to the present invention is shown.

[0050] Figure 3 A possible embodiment of the head coil device according to the present invention is shown.

[0051] Figure 4 A possible embodiment of the head coil device according to the present invention is shown.

[0052] Figure 5 A possible embodiment of the head coil device according to the present invention is shown.

[0053] Figure 6 A possible embodiment of the head coil device according to the present invention is shown. DETAILED DESCRIPTION

[0054] exist Figure 1 1 shows a magnetic resonance device 10, which includes an examination bed 13 and a magnetic resonance tomograph 9. The examination bed 13 has a non-movable part 22 of the examination bed 13 and a movable part 23 of the examination bed 13. The patient 11 is positioned on the movable part 23 of the examination bed 13, which can be moved into a patient tunnel 21 of the magnetic resonance tomograph 9 for performing a magnetic resonance examination. In addition, there is a head coil device 24 on the movable part 23 of the examination bed 13, which includes a receiving coil unit 26 (not shown) and a transmitting coil unit 25, and receives the head of the patient 11. The head coil device 24 is preferably connected to the movable part 23 of the examination bed 13 in a predetermined position. Therefore, the movable part 23 of the examination bed 13 and the head coil unit 24 can be moved relative to the magnetic resonance tomograph 9 and the non-movable part 22 of the examination bed 13. In order to receive the head of the patient 11, the transmitting coil unit 25 and / or the receiving coil unit 26 can be positioned relative to the head coil device 24.

[0055] Figure 2A possible embodiment of the head coil device 24 according to the invention in the patient tunnel 21 of the magnetic resonance device 10 according to the invention is shown. The head of the patient 11 is supported in the head coil device 24. In the example shown, the patient 11 lies on his back on the movable part 23 of the examination bed 13 and is surrounded on the outer circumference by the wall of the patient tunnel 21 of the magnetic resonance device 10. The transmission coil unit 25 completely surrounds the reception coil unit 26 of the head coil device 24 and limits the field of vision of the patient 11. The head coil device 24 has a stop point 33 and a linear guide device 31. In the example shown, the transmission coil unit 25 is carried by two holders 32 on the linear guide device and can be moved in a linear manner on the linear guide device along the longitudinal direction 12 of the patient 11. The movement path of the linear guide device 31 is terminated at both ends by the stop points 33, and the transmission coil unit 25 cannot pass through the stop points. In the example shown, the transmission coil unit 25 is in a measurement position above the head of the patient 11. The magnetic resonance device 10 has a guide element 42, which can be in mechanical contact with the driving member 41 of the transmitting coil unit 25. In the present example, the driving member 41 is connected to the transmitting coil unit 25 in an immovable manner. If the movable part 23 of the examination bed 13 is moved out in the direction of the patient tunnel 21, the driving member 41 contacts the guide element 42 at a defined point. The guide element 42 is preferably positioned immovably on the inner side of the patient tunnel 21 and therefore opposes the driving member with a resistance force, which can correspond to the friction force of the transmitting coil unit 25 on the linear guide device 31. Since the transmitting coil unit 25 is movably supported on the linear guide device 31, the transmitting coil unit 25 is moved into the measuring position in the direction of the patient 11 when the examination bed 13 moves. In accordance with Figure 2 In the specific embodiment of , the measuring position corresponds simultaneously to the end position of the transmitting coil unit 25 , since the transmitting coil unit cannot be moved beyond the stop point 33 .

[0056] Figure 3The head coil device 24 according to the invention is shown when the movable part 23 of the examination couch 13 is moved out of the patient tunnel 21. The guide element 42 is positioned on the immovable part 22 of the examination couch 13 so that it contacts the driver 41 of the transmission coil unit 25 at a defined point. Since the transmission coil unit 25 is movably supported on the linear guide 31, it is held in one position by the guide element 42 during the movement of the movable part 23 of the examination couch 13 with the head coil device 24 out of the patient tunnel 21. Since the reception coil unit 26 is not connected to the transmission coil unit 25 in the example shown, it is held in the measuring position and is moved out of the patient tunnel 21 with the head coil device 24. The reception coil unit 26 preferably has a nose cutout 27, an eye cutout 28 and a mirror 29. As a result, the field of vision of the patient 11 is only slightly restricted, so that it is generally not necessary to consider the examination being interrupted by the patient 11. In the example described, the receiving coil unit 26 is moved from the measuring position to the starting position via an independent mechanism. It is conceivable that the receiving coil unit 26 can be moved manually in the transmitting coil unit 25. It is also conceivable that the receiving coil unit 26 is supported together with the transmitting coil unit 25 on the linear guide 31 of the head coil device 24 or has an independent linear guide. Figure 3 The cross section through the wall of the receiving coil unit 26 in FIG. 2 schematically shows how the coil 14 can be integrated into the receiving coil unit 26 . An integration in a similar manner is also conceivable in the transmitting coil unit 25 .

[0057] exist Figure 4, an embodiment of a head coil device 24 is shown, in which a transmitting coil unit 25 and a receiving coil unit 26 are connected to one another in a predetermined position. Preferably, the receiving coil unit 26 is connected to the transmitting coil unit 25 in a form-fitting manner and can be moved together with the transmitting coil unit 25 on a linear guide 31 of the head coil device 24. In this embodiment, the field of vision of the patient 11 is limited only when the movable part 23 of the examination bed 13 moves into the patient tunnel 21. As a result, the patient 11 can always maintain eye contact with the medical staff until the eye contact is interrupted by the patient tunnel 21. The guide element 42 in the patient tunnel 21 is preferably positioned so that the composite composed of the transmitting coil unit 25 and the receiving coil unit 26 moves only into the measuring position in the patient tunnel 21. It is conceivable that the head coil device 24 has a fixing device (not shown), for example a lateral support or a shaped neck pillow that limits the movement of the head in the head coil device 24. The patient's head can thereby be supported in a correct position, which preferably corresponds to the measuring position of the transmission coil unit 25 and the reception coil unit 26. Furthermore, by fixing the head it can be ensured that the patient 11 is not injured by automatic movements of the transmission coil unit 25.

[0058] Figure 5 An embodiment is shown in which the driver 41 has an elastic material. The driver 41 is deformed by contact with the guide element 42 of the magnetic resonance device 10. The force required for deforming the elastic material is preferably greater than the static friction of the transmission coil unit 25, so that when the movable part 23 of the examination bed 13 moves in the direction of the patient tunnel 21, the transmission coil unit moves into the measuring position. In the example shown, if the transmission coil unit 25 abuts at the stop point 33, the force acting on the driver 41 increases when the movable part 23 of the examination bed 13 moves forward. The force acting on the driver 41 can eventually be so great that the driver is further deformed and slides past the guide element 42. Then, the transmission coil unit 25 is in the measuring position, and the patient 11 can move further into the patient tunnel 21. In the opposite movement of the examination bed, for example, when the patient 11 moves out of the patient tunnel 21, the driver 41 can mechanically contact the guide element 42 from the opposite side. As a result, the transmission coil unit 25 is automatically moved with the movement of the movable part 23 of the examination bed 13 from the measuring position to the starting position, which is located at a stop point 33 (not shown) at the opposite end of the linear guide 31 .

[0059] In one possible embodiment, a motor 43 is provided which can move the transmission coil unit directly or via the drive device 25. Figure 6In the example, the motor 43 is positioned on the immovable part 22 of the examination bed 13. The motor 43 drives the screw 31, which at the same time serves as a linear guide 31 for the transmitting coil unit 25. For this purpose, the holder 32 can have a thread, which engages in the thread of the screw 31. The rotational movement of the screw 31 causes the transmitting coil unit 25 to be transported by moving the holder 32 along the screw 31. In the example, the direction of movement of the transmitting coil unit 25 can be set via the direction of rotation of the motor 43. The screw 31 and the holder 32 can, for example, be made of plastic. The motor can be positioned on the immovable part 22 of the examination bed 13 outside the magnetic field of the magnetic resonance device 10. In Figure 6 In the embodiment, the holder 32 simultaneously realizes the function of the driver 41, by means of which the movement and / or the force are transmitted to the transmission coil unit 25. In addition to the screw 31, other drive devices are also conceivable, such as belts, gears and hydraulic or pneumatic working elements.

Claims

1. A head coil device (24) for a magnetic resonance device (10), the head coil device comprising a transmitting coil unit (25) and a receiving coil unit (26), The transmitting coil unit (25) is configured to be automatically positioned relative to the receiving coil unit in the longitudinal direction of the patient in such a way that the transmitting coil unit is moved relative to the receiving coil unit and the receiving coil unit can be positioned in a predefined measuring position above the patient's head.

2. The head coil device (24) according to claim 1, wherein the head coil device (24) has a linear guide device (31), by means of which the transmission coil unit (25) can be freely positioned on a defined movement path.

3. A head coil device (24) according to claim 1, wherein the transmitting coil unit (25) is pivotably supported on the head coil device (24) at a maximum angle relative to the head coil device (24), wherein the maximum angle between the transmitting coil unit (25) and the head coil device (24) is selected so that the head of the patient (11) can be positioned in the head coil device (24) without hindrance.

4. A head coil device (24) according to any one of the preceding claims, wherein the head coil device (24) has a drive device for moving the transmitting coil unit (25), and the drive device applies a force to the transmitting coil unit (25) so that the transmitting coil unit moves along a movement path.

5. The head coil device (24) according to claim 4, wherein the drive device for moving the transmission coil unit (25) is a hydraulic or pneumatic drive device.

6. The head coil arrangement (24) according to claim 4, wherein the drive device for moving the transmission coil unit (25) comprises a motor (43).

7. The head coil device (24) according to claim 2, wherein the head coil device (24) and / or the transmitting coil unit (25) have a mechanical damping element, which is designed to accommodate the transmitting coil unit (25) in a vibration-damping manner at a stop point of the movement path.

8. The head coil device (24) according to any one of claims 1 to 3, wherein the transmitting coil unit (25) has a driver (41), wherein: The driver (41) is designed to transmit force when in mechanical contact with a guide element (42) of the magnetic resonance system (10), wherein the transmission coil unit (25) can be positioned by means of the force transmission.

9. The head coil arrangement (24) according to claim 8, wherein the driver (41) is connected to a drive device and is designed to transmit a movement to the transmission coil unit (25).

10. The head coil device (24) according to claim 8, wherein the driver (41) is designed to change the value of the force acting on the guide element (42) in the direction of movement of the transmission coil unit (25) as a function of the position of the transmission coil unit (25).

11. The head coil arrangement (24) according to claim 8, wherein the driver (41) is designed to change the direction of the force acting on the guide element (42) as a function of the position of the transmission coil unit (25).

12. The head coil device (24) according to any one of claims 1 to 3, wherein the transmitting coil unit (25) and the receiving coil unit (26) are connected to each other in a predetermined position and can be positioned relative to the head coil device (24).

13. A magnetic resonance system (10) having a head coil arrangement (24) according to claim 1, It is characterized in that The transmission coil unit (25) can be automatically positioned, wherein the magnetic resonance system (10) comprises a guide element (42) which is designed to transmit a force to a driver (41), wherein the transmission coil unit (25) can be positioned by means of the force acting on the driver (41).

14. A magnetic resonance system (10) according to claim 13, wherein the guide element (42) is designed to change the direction of the force acting on the driving member (41) and / or the value of the force acting on the driving member (41) in the direction of movement of the transmitting coil unit (25) depending on the position of the transmitting coil unit (25).

15. The magnetic resonance system (10) according to claim 13 , wherein the magnetic resonance system (10) comprises an examination bed (13), wherein the examination bed (13) comprises a guide element (42) which forms a driver (41) for transmitting a force to the transmission coil unit (25).

16. The magnetic resonance system (10) according to claim 13, wherein the magnetic resonance system (10) comprises a drive device which is connected to the guide element (42) and exerts a force on a driver (41) of the transmission coil unit (25).

17. The magnetic resonance system (10) according to claim 16, wherein the drive of the guide element (42) is connected to a motor (43).

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