A system for acquiring images using intraoperative magnetic resonance imaging.

Abstract

A system for acquiring images by intraoperative magnetic resonance imaging, particularly for the purpose of obtaining images to confirm the progress of brain surgery. The system comprises a magnetic structure that generates a static magnetic field and partitions or surrounds, on at least some sides, a containment space for containing at least the patient's head, and a bed that is movable to different relative positions with respect to the magnetic structure, the positions being between an end position where the bed is at least partially inside the containment space and an outer end position where the bed is outside the containment space and at a predetermined distance from the magnetic structure. The bed is cantilevered by the column and is capable of rotational movement at least in the angular direction relative to the column, thereby allowing the bed to swing continuously between two end positions. One of the two end positions is defined as the imaging position, where the bed end opposite the outer end is positioned within the patient's accommodation space and the patient's head is positioned in the correct image acquisition position relative to the magnetic structure; and the other of the two end positions is positioned at a predetermined distance from the magnetic structure and is in the surgical position.

Description

Technical Field

[0001] The present invention relates to a system for acquiring images by intraoperative magnetic resonance imaging (MRI), and particularly to a system for acquiring images for controlling and confirming the progress during brain surgery. This system includes a magnetic structure configured to generate a static magnetic field and to partition or surround an accommodation space for at least part of a patient's head, and a movable bed that can be moved to different relative positions with respect to the magnetic structure, the positions including an inner end position where the bed is at least partially located within the accommodation space and an outer end position where the bed is outside the accommodation space and maintains a predetermined distance from the magnetic structure.

Background Art

[0002] In the field of surgery, particularly in brain surgery, it is common to alternately perform the surgical procedure and the step of checking the condition of the site where the surgery was performed using magnetic resonance imaging (MRI). In such a case, after several steps of the surgery or when the surgeon determines it is necessary, the surgery is temporarily interrupted, and the patient is moved into the accommodation space of the MRI device to obtain diagnostic images for confirmation.

[0003] In brain surgery, as is known in the prior art, in order to prevent the patient's head from shifting relative to a reference position, also called the position of a surgical instrument that requires positioning with extremely high accuracy, the patient's head is firmly fixed to the bed. Therefore, when the surgical procedure is temporarily interrupted and control imaging is performed, it is desirable not to move the patient from the operating table dedicated to surgery to the bed of the MRI device or vice versa.

[0004] Therefore, one solution is to configure the couch of the MRI machine to serve both as an operating table and as a patient positioning bed within the MRI machine. Typically, in such a configuration, the bed may be moved alternately between a position outside the magnetic structure, maintaining a predetermined distance, for performing surgical procedures, and a position inside the patient occupancy space for acquiring confirmation images. All vital sign monitoring devices, drug administration devices, and various systems and tools used in performing surgical procedures (such as positioning systems and instrument guidance systems) must be associated with the bed to avoid interference with the magnetic field generated by the MRI machine's magnetic structure. In particular, if the magnetic structure is of the permanent magnet type, it is necessary to position the bed at a predetermined distance or more away from the MRI machine's magnetic structure, where the strength of the magnetic field generated by the permanent magnet is very low and does not affect the equipment and tools necessary for surgery. The bed of the MRI machine must be equipped with a device called a craniostat. This craniosac is a device used to fix the position of the skull, and it needs to remain securely and stably attached to the patient's skull throughout the entire duration of the surgery.

[0005] Acquiring MRI images requires a coil to receive magnetic resonance signals, which is preferably positioned near the anatomical site being examined, in this case, the head. Therefore, the coil must be correctly positioned on the patient for image acquisition and then removed to allow access to the surgical field.

[0006] A third important point in implementing the aforementioned surgical method, which involves alternating between surgery and image acquisition for confirmation, is the overall duration of the surgery. Since this surgery time must be kept within a predetermined time, it is necessary to minimize the time required for image acquisition. Furthermore, the interruption time between each surgical step should be kept as short as possible to avoid excessively extending the overall surgery time and to prevent unnecessarily long anesthesia times due to excessively long intervals between surgical steps.

[0007] In the case of image acquisition using nuclear magnetic resonance imaging, especially in soft tissue imaging, it is difficult to shorten the acquisition time in order to obtain high-quality images that can accurately represent the condition of the surgical site. Therefore, it is impossible, or almost impossible, to shorten the time of the image acquisition process itself in order to shorten the time between a surgical procedure and the subsequent acquisition of confirmation images. Thus, in order to shorten the time interval from one surgical procedure to the next, it is necessary to shorten the transition time between the surgical position and the patient's imaging position. This transition must be carried out quickly so that the patient, and by extension the bed, can move beyond a predetermined minimum distance set to avoid the magnetic field leaking outside the MRI device's magnetic structure interfering with the internal containment space of the device, or vice versa.

[0008] Conventional technologies include several solutions that describe moving a magnet to the surgical station for performing neurosurgical procedures. These methods alternate between surgical procedures and imaging of the surgical field, allowing for monitoring or confirmation of the state of the surgical field after each procedure, and enabling planning of at least the next surgical procedure.

[0009] Devices for fixing a patient's head to the operating table during brain surgery are also known as conventional technology.

[0010] While specialized receiving coils are known for head magnetic resonance imaging, most are incompatible with the patient's head fixation devices. They must be attached to the patient's head during MRI image acquisition and removed during the surgical procedure, further increasing the required time.

[0011] U.S. Patent Application Publication No. 2010 / 102814 discloses a combination of an MRI apparatus and a patient table according to the preamble of claim 1.

[0012] This publication discloses an MRI apparatus having an open U-shaped or C-shaped magnetic structure. The magnetic structure comprises at least one vertical connecting member for connecting two horizontal wall members arranged vertically, the horizontal wall members being cantilevered by the vertical connecting member and spaced apart. Furthermore, the vertical connecting member is eccentrically connected to the side edges of the two horizontal wall members. The horizontal wall members and vertical connecting member define the upper, lower, and at least a portion of the vertical side bands of a space that accommodates at least a portion of the patient's body. The horizontal wall members also support means for forming a static magnetic field in the patient occupancy space. The apparatus further comprises a patient table supported at an intermediate position between the two horizontal wall members and located directly above the lower horizontal wall member. The table is displaceable in at least one direction of movement, the movement including a component toward / away from the vertical connecting member. The table is also rotatable about a vertical axis located outside the magnetic structure, i.e., the horizontal wall members.

[0013] Japanese Patent Publication No. 2000-232969 discloses a combination of an MRI apparatus and a patient support table. In this apparatus, the patient support table rotates around a vertical rotation axis located at the table end, which is located outside the imaging gantry of the MRI apparatus. The disclosed rotation angle is 90°, as shown in Figure 16.

[0014] German Patent Application Publication No. 19736884 discloses a combination of an MRI apparatus and a patient table that can be positioned either inside or outside the gantry of the MRI apparatus by rotational motion of the table in a horizontal plane. The position of the end of the patient table outside the gantry of the MRI apparatus is shown to be at a certain distance from the magnetic structure of the MRI apparatus. Furthermore, this combination of MRI apparatus and patient table is configured such that a table rotation of more than 90°, particularly 180°, is required to position the end of the table at a predetermined distance from the magnet, and to ensure that the magnetic flux intensity diffusing outside the gantry of the MRI apparatus at that distance is below a predetermined level.

[0015] U.S. Patent Application Publication No. 2019 / 374417 discloses a medical system comprising a robotic surgical tabletop and a controller. The robotic surgical table has a robotic arm that supports the tabletop. The controller commands the robotic arm to move the tabletop to a position corresponding to a medical procedure. The robotic arm includes a plurality of joints, a plurality of movable elements connected to each other by the plurality of joints, a plurality of electric actuators, and a plurality of position sensors. These joints include two joints configured to connect the elements so as to be rotatable in the horizontal direction. These two joints each have different axes of rotation and are located a certain distance apart from each other, specifically one at the edge of the tabletop and the other in the center of the tabletop. The patient is positioned lying on the tabletop, either inside the gantry of an MRI machine or outside the gantry of a surgical station, by the combined rotation of the movable elements around these two axes of rotation. Furthermore, the tabletop is connected to the robotic arm via joints that allow the tabletop to be tilted to different angles relative to the horizontal plane.

[0016] U.S. Patent No. 5,085,219 discloses an MRI RF coil holder for imaging the temporomandibular joint. The invention provides elements for positioning and fixing an RF surface coil at a first predetermined position along the longitudinal axis of a patient positioning table and holder, and for positioning and fixing it at a second predetermined position perpendicular to the longitudinal axis and at a radius R from the longitudinal axis. In the disclosed embodiment, the surface coil can be orbited around the longitudinal axis by positioning a U-shaped runner guide substantially perpendicular to the longitudinal axis and cooperating an adjustable clamp with the runner guide. Furthermore, the surface coil can be adjusted along a path perpendicular to the longitudinal axis using an adjustment shaft or arm that is movable inward and outward. The surface coil can also be rotated in steps using a pivot head having a plurality of equally spaced positioning notches (dentents). The pivot head is biased away from the surface coil and rotates around an axis substantially parallel to the longitudinal axis, adjustingly engaging with one of the plurality of dentents.

[0017] U.S. Patent No. 5,735,278 discloses a patient support table. The table has two opposite ends, one of which is configured to form a seat for positioning a patient's head. This end is formed by the end portion of the patient positioning table and is hinged to swing around a horizontal axis and connected to the rest of the table body.

[0018] The disclosed prior art situation is not such that the disclosed combination of features is designed to reduce the time required to move a patient from the surgical site into or from the gantry of an MRI machine, nor is it designed to reduce costs through a simpler and more efficient structure, nor is it designed to avoid imposing a complex burden on service personnel regarding the operation of the patient positioning device. [Overview of the project]

[0019] The object of the present invention is to provide a system for acquiring intraoperative magnetic resonance imaging, particularly for intraoperative imaging in head surgery, and more particularly in brain surgery, which enables faster, easier, and more convenient MRI image acquisition operations during the interruption time between two surgical steps in a series of surgical procedures.

[0020] In the first embodiment of the present invention, the system is A magnetic structure that generates a static magnetic field and partitions or surrounds, on at least some sides, a containment space for accommodating at least the patient's head, A bed that can move to different relative positions with respect to the magnetic structure, Equipped with, The aforementioned position is located between an end position in which the bed is at least partially within the accommodation space and an outer end position in which the bed is outside the accommodation space and at a predetermined distance from the magnetic structure. It is a system, The magnetic structure has a horizontal U-shaped or C-shaped cross-section, The magnetic structure comprises at least one vertical connecting element connecting two horizontal wall elements separated vertically from each other, and the two horizontal wall elements are cantilevered by the vertical element at a predetermined distance from each other. The aforementioned vertical element is connected to the two wall elements at its side ends in a manner offset from the center. The horizontal wall element and the vertical element define a containment space for accommodating at least a portion of the patient's body in the upper, lower, and at least one vertical side. The horizontal wall element is equipped with a means for generating a static magnetic field that penetrates the containment space, The patient support bed is located outside the magnetic structure and has one end positioned at a predetermined distance from the magnetic structure. The aforementioned patient support bed is cantilevered at the opposite end by a column, The column is connected to the bed in the region of the outer end, and the patient support bed is rotatable about a vertical axis that coincides with or is parallel to the axis of the column, whereby the bed can be continuously swung between two end positions. The bed can be continuously swung between two end positions with respect to a predetermined angular path. The bed can be continuously swung between the two end positions. One of the two end positions is defined as an imaging position, and at the imaging position, the bed end opposite the outer end includes the patient's head positioning region, and the outer end is disposed within the accommodation space of the patient of the magnetic structure, and the patient's head positioning region is disposed at a correct image acquisition position with respect to the magnetic structure. In the other of the two end positions, the bed end of the patient support bed opposite the outer end is disposed at a predetermined distance from the magnetic structure and is at the position of the surgical station. The swing angle path of the patient support bed is less than 90° and is only around the vertical rotation axis.

[0021] For this configuration, various structural modifications can be provided to achieve similar functions.

[0022] As a structural variation, alternatively or in combination and in a freely selectable form, manual movement along the angular path of the bed can be provided, and / or an electric drive element used in combination with the operation and stop commands of the drive element can also be provided.

[0023] According to an advantageous embodiment, the distance with respect to the central vertical axis of the magnetic structure is selected such that when the bed is rotated to a position within the magnetic structure, the patient's head positioning region coincides with a so-called imaging volume with respect to the magnetic structure. The imaging volume is a part of the entire volume of the accommodation space of the patient such that a useful and high-quality diagnostic image can be obtained because the static magnetic field generated by the permanent magnet has sufficient uniformity. Thereby, the head of the patient lying on the patient support bed is placed at a position that coincides with the imaging volume.

[0024] Furthermore, in combination with the above, the distance and the rotation angle around the vertical rotation axis of the bed are such that at the outer end position, the end of the bed corresponding to the head positioning region of the patient is at a position where the influence of the static magnetic field penetrating from the magnetic structure at this position is below a predetermined intensity value and does not interfere with the devices and the surgical unit required for the surgery.

[0025] According to one embodiment, when the end position of the patient support bed where the end provided with the head positioning region of the patient is located coincides with the surgical position of the surgical station, at the head positioning region of the patient and the end position of the surgical station, the magnetic field intensity transmitted from the gantry of the magnetic structure or the magnetic structure of the MRI device is outside the 5-gauss equipotential line of the magnetic field generated by the magnetic structure (as shown in FIG. 3 of the accompanying drawings), which means that the magnetic field intensity is preferably not higher than 5 gauss or lower than 5 gauss.

[0026] In order to stabilize the bed supported cantilevered from the column, the column can be provided with a ballast for offsetting the weight of the bed projecting cantilevered on the column and / or the column can be provided with feet to be fixed to the floor.

[0027] Alternatively or in combination, a wheeled support can be arranged in the region of the cantilever bed to enhance the stability of the bed and limit the deflection in the region inside the gantry. The support can be configured integrally with the bed or detachably.

[0028] In addition to configurations that allow movement in the angular direction, it is also possible to configure the bed to be able to move based on other degrees of freedom.

[0029] Alternatively or in combination with the above, according to one embodiment, the bed is vertically movable, for example, by making the support column a telescopic structure that can extend and retract. The extension and / or shortening of the column can be advantageously driven by a dedicated gear motor unit or a linear actuator (such as an electromechanical linear actuator or a hydraulic or pneumatic actuator).

[0030] According to further features that can be provided in combination with one or more features, the bed may be configured to be extendable and / or linearly movable relative to the support column, thereby changing, at the user's discretion, not only the total length and / or circumferential path of the bed end intended to enter the magnetic structure, but also the position of the bed end relative to the column corresponding to the head.

[0031] Furthermore, according to features that can be provided by arbitrarily combining or partially combining the above-mentioned features, the bed can be supported so as to be able to rotate about a substantially horizontal axis, that is, so as to be able to rotate from top to bottom or vice versa.

[0032] For this purpose, a swing joint can be provided between the bed and the end of the connecting column to the bed, along at least one axis, and can be configured in a manner that is not limited to an axis along at least one axis oriented laterally with respect to the longitudinal direction of the patient support bed. The swing is produced by moving the end relative to the column upward, or conversely, by moving the end downward.

[0033] Furthermore, according to additional features that can be provided in place of, or in any combination or in part with, the above-described features, the end section of the bed opposite the column is comprised of an end zone hinged to swing around a horizontal axis perpendicular to the longitudinal direction of the patient support bed, thereby allowing the end section to swing upward and / or downward around the horizontal axis relative to the rest of the bed.

[0034] All of the above movements can be controlled by electric actuators and / or hydraulic or pneumatic actuators, and can be performed at least partially simultaneously, sequentially, and / or partially overlapping for each element. These movements allow the bed to be moved easily and quickly from the surgical station to the imaging station and vice versa, as well as to be positioned quickly and easily according to multiple degrees of freedom. Specifically, the bed can be moved from a height that is convenient for the surgeon to work at the surgical station to a position that is vertically aligned with the bed housing space within the magnetic structure. Furthermore, the entire bed, or at least the portion corresponding to the patient's head, can be tilted relative to the horizontal position, allowing for adjustment of blood flow, such as reducing blood flow to the brain to facilitate securing a surgical field of view.

[0035] According to one embodiment, a craniosac, or cranial stabilization device, for fixing the patient's head to the bed is fixedly or detachably attached to the bed. The head positioning or restraining device (craniosac) is provided in combination with an MRI signal receiving coil, the receiving coil being formed by a single element or a plurality of electrically connected elements. The elements are detachably attached at predetermined positions to at least a portion of the structural members of the craniosac, and constitute a receiving coil for the head when attached to the craniosac.

[0036] In a modified embodiment, the craniosac comprises an anatomical support base that supports the back of the patient's head and at least two curved lateral elements extending from the support base toward the corresponding temples of the patient, with a cranial clamping device provided at a predetermined position on the lateral side that can move the patient's head between a clamping and a release position. The base and / or lateral elements are also provided with hook-shaped and / or mating seats for housing individual coil elements, which are formed as solid plates and / or annular plates, with conductors forming a coil and conductors at the ends of the plates incorporated within each plate, which begin and end with connector terminals for jumpers, and the conductors of each plate are connected to each other by the jumpers, so that the circuits formed by the individual plates constitute the circuit of the entire coil.

[0037] Alternatively, the base of the craniosacral stat for the patient's head has two wings (two coil hemishells) hinged to each of the temporal regions, allowing them to swing between an open coil position and a closed position. In the open coil position, the wings (hemishells) swing to open laterally toward the bed, and in the closed position, the wings (hemishells) swing opposite each other to form a cup-shaped element surrounding the patient's skull. Each of the two wings (hemishells) houses a portion of the coil conductor, and the edges facing each other in the closed position are equipped with terminals for temporary and detachable mechanical and electrical connections, thereby electrically connecting the conductor segments of the two wings (two hemishells) to form the entire coil circuit, and the two wings (two hemishells) are connected to each other via detachable mechanical connections. Note that the two hemishells do not necessarily need to be mechanically connected to form a single receiving channel; they can form independent surface receiving channels and be phase-complementary.

[0038] In a modified version, the receiving coil segment may consist of at least one surrounding band of the cranial support base and include a segment of coil conductors extending between the two hinge sides of the wing (half-shell). The ends of the coil segments are provided with electrical terminals that are flexible or movable in the direction of oscillation, which are connected to corresponding terminals of the coil segments within the wing (half-shell). These terminals are positioned to coincide with the flexible terminals of the coil conductor segment ends within the housing base.

[0039] The above embodiments are highly diverse and always remain within the conceptual framework of integrating the coil circuit into a structure that is fixed to the head fixture (craniostat) in an openable and closable manner, or into a structure consisting of one or more elements that can be attached to and detached from the craniostat structure.

[0040] In the modified implementation, the receiving coil has an annular shape and can be secured to the patient's head and / or craniosac using a clamping band or belt, and the inner diameter and planar shape of the annular shape are set so that at least the surgical field is contained within the opening, thus allowing access to the surgical field even when the receiving coil is attached to the patient's head.

[0041] Furthermore, according to one embodiment of the present invention, which can be provided in any combination with any of the above embodiments and / or modifications, the patient is monitored during surgery by a plurality of physiological parameter monitoring units, these parameters are detected by probes attached to the patient, and furthermore, one or more drugs of different properties are administered during surgery, so the patient is connected to the monitoring units and / or drug administration / supply units via a plurality of electrical cables and / or fluid supply hoses. The bed is provided with elements on at least a portion of its surface extension and / or at least a portion of its periphery for detachably fixing or holding the cables and / or tubes, the cables and / or tubes having redundant length and being able to follow the movement of the bed, in particular rotation between the two end positions.

[0042] In one preferred embodiment, the patient support bed may have one or more accommodating channels having a closed annular section or an open section with a closure element, extending along the entire length or a portion of the longitudinal extension of the channel. The accommodating channels are located on at least one longitudinal side and adjacent to at least a portion of its side edge, or integrated into a portion of at least one side edge of the bed, or further located along the bottom surface of the bed and on one or both side edges.

[0043] According to yet another possible alternative, the patient support bed may be integrated into its structure.

[0044] In each of the above alternative examples, the bed structure and / or the walls of one or more channels may include electrical and / or electromagnetic shielding, thereby preventing cables and piping from interfering with the magnetic field and / or the transmit / receive coils of the MRI device.

[0045] In this way, by manipulating the bed with the patient in the position necessary for surgery, the strength of the magnetic field leaking from the magnetic structure can be kept below a predetermined threshold, thus eliminating the problem of cables and / or tubes becoming excessively long in order to not limit the relative distance between the surgical station and the imaging station, or overcoming the problem of having to anticipate excessive excess length of cables and / or tubes, including the cable connecting the receiving coil to the device.

[0046] Further features of the present invention are covered by the dependent claims. These and other features and advantages of the present invention will be more clearly understood from the following description of some embodiments shown in the accompanying drawings. [Brief explanation of the drawing]

[0047] [Figure 1]Figure 1 shows a perspective view of the intraoperative MRI system according to the present invention (i.e., a system for acquiring MRI images during intervals in the workflow of the surgical process). [Figure 2] Figure 2 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 3] Figure 3 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, and can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 4] Figure 4 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 5] Figure 5 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 6] Figure 6 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 7] Figure 7 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 8] Figure 8 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 9] Figure 9 illustrates different degrees of freedom regarding the movement of the bed relative to the magnetic structure of the MRI apparatus, which can be provided in place of or in combination with the bed rotation shown in Figures 2 and 3. [Figure 10] Figure 10 shows an alternative embodiment of the head receiving coil. [Figure 11]Figure 11 shows an alternative embodiment of the head receiving coil. [Modes for carrying out the invention]

[0048] Referring to the figure, the nuclear magnetic resonance imaging apparatus comprises a magnetic structure 1 and a patient support bed 2. In this description, preface, and claims, for simplicity, the term "magnetic structure" generally refers to the yoke, static magnetic field generating means, poles, and the portion including gradient coils, compensating coils, electromagnetic shields, temperature measuring and / or temperature control means, and other components typically provided in this type of apparatus, and further includes a cover portion that protects these components from the outside. As described later, this cover consists of wall elements that form part of an outer shell, which has the function of protecting the equipment, patient, and user, and further has the function of fixing components that do not contribute to the excitation and reception of signals used for image generation, and for aesthetic reasons. This simplification should be understood as clear and unquestionable to those skilled in the art, and the expression "magnetic structure" should be considered equivalent as a pars pro toto (parts representing the whole) term. That is, it essentially determines the shape and dimensions, and additional components are generally mounted on the structure, merely determining the increase or decrease in the thickness of the patient accommodation cavity CV.

[0049] It is also worth noting that the present invention refers to a magnetic structure in which the two poles are perfectly horizontal, and that the patient-supporting surface of the bed is horizontal. However, it is possible to provide a similar structure even when the poles are inclined to some extent with respect to the horizontal plane, or when the poles are not planar.

[0050] As described above and with reference to the drawings, the magnetic structure or magnet of the MRI apparatus is C-shaped or inverted U-shaped, with two horizontal branches separated from each other on one side by a vertical element 301. These two horizontal branches form wall elements 101 and 201, partitioning the accommodation space CV for the patient or a part thereof in both the vertical and horizontal directions. In particular, in the shown diagram, the spacing between the two branches of the magnetic structure is set so that even the torso portion of the patient can be introduced into the accommodation space (cavity) CV. These two branches are formed by horizontal yoke branches, and means for generating a magnetic field are arranged on the faces opposite each other. Specifically, these include layers of magnetizing material, poles made of plates of iron magnetic material, various coils that generate a variable magnetic field (so-called gradient coils), coils that transmit nuclear spin excitation pulses, and other operating units (shielding means, temperature measuring means, etc.). A static magnetic field B0 is generated between the two horizontal branches. The vertical wall element 301 consists of a vertical yoke element and an additional layer of magnetizing material or iron magnetic material, contributing to the optimization of the static magnetic field B0. All of these elements are covered by an external protective shell, giving the device an aesthetically pleasing appearance.

[0051] The static magnetic field B0 is not ideal for image acquisition across the entire horizontal wall elements 101 and 201. On the other hand, the static magnetic field B0 can satisfy desired properties, particularly uniformity, in a partial volume of the entire cavity. This partial volume is defined as the region enclosed by the surface of an ideal sphere or ellipsoid, and is called the "imaging volume," schematically shown in the figure and denoted as V.

[0052] The magnetic structure is configured in combination with a bed 2 having a nearly horizontal patient support surface 102. The bed is cantilevered at the outer end of the magnetic structure 1 by vertical supports 202, which are equipped with appropriate ballast or are fixed to the floor (indicated by legs 502) to prevent the bed from tilting when a patient is placed on it.

[0053] The columns are of a height that allows the bed to fit between the two horizontal walls 101 and 201, or are adjustable to that length, and are particularly designed to fit at the upper level of the lower horizontal wall element 201. In this way, the bed is inserted into the patient cavity CV by moving laterally relative to its longitudinal direction, and at the same time becomes cantilevered within the patient cavity.

[0054] Based on the illustrated configuration, one of the support elements of the patient support surface 102 is designed so that the patient support surface 102 can rotate about a vertical axis V, that is, in a direction perpendicular to the bed support surface. The arrangement of this axis is such that the axis of rotation coincides with the end of the bed connected to the column 202, which is designed to serve as a seat for housing a joint to which the connected end is fixed to the bed, and this joint is structured to rotate about the vertical axis V.

[0055] Column 202 is positioned on the outside of the magnetic structure, and in particular, along one of the sides of the magnetic structure. This side is oriented parallel to the plane of the vertical cross-section that intersects the horizontal and vertical branches of the magnetic structure, along which the C-shaped or U-shaped cross-section branches of the magnetic structure extend.

[0056] In the following description, these sides will be simply referred to as the lateral flanks S1 and S2 of the magnetic structure, and the remaining two sides will be referred to as the open front side and the closed rear side.

[0057] The pivot axis is positioned within the projection of the widthwise dimensions of the upper and lower horizontal wall elements 101 and 201, and perpendicular to the aforementioned side wings. The distance of the magnetic structure from the corresponding side wings is set such that the vertical support element 302, located at the opposite end of the patient support surface 102, is adjacent to the side wing S1 on the opposite side of the magnetic structure. As a result, when the bed oscillates, the patient support surface moves along a concentric trajectory centered on the pivot axis 0, and this pivot axis is located outside the magnetic structure. This allows the patient support surface to enter the patient occupancy cavity CV almost directly from the open front side of the magnetic structure, and the patient can also move into the cavity.

[0058] As will become clear from the following explanation, in addition to rotational motion relative to the magnetic structure, the bed may have additional degrees of freedom, either interchangeable with each other or as any combination or partial combination of these degrees of freedom.

[0059] In one embodiment, the leg 502 may be designed as a carriage equipped with wheels that can be locked or retracted relative to the leg itself, and by switching the operation and deactivation of these wheels, the leg 502, and consequently the vertical support element 202, can be made movable or fixed in position. Preferably, the leg 502 may be equipped with a carriage constrained to a guide or rail fixed to the floor.

[0060] This allows for easy adjustment of the position of the bed, particularly the vertical support element 202 of the bed, and the position of the bed's vertical rotation axis relative to the magnetic structure. As a result, the imaging system can be adapted to different station configurations outside the system for arranging the operational units required for surgical work.

[0061] In particular, the position of the rotating axis of the magnetic structure with respect to the central vertical axis is selected such that, by rotation, the end of the bed, especially the side opposite to the side fixed to the column 202 and on which the patient's head fixation device 602 is placed, rotates and moves into the patient accommodation cavity of the magnetic structure 1, and is positioned to coincide with the imaging volume V, and further to coincide with the surgical station. In particular, at the position coincide with the surgical station, the ends of the bed associated with the station and the patient's head position stabilization and fixation device are set to be sufficiently far from the magnetic field penetrating outside the magnetic structure, which is especially effective in the case of magnetic structures of the type in which the magnetic field is generated by permanent magnets.

[0062] In particular, the distance of the surgical station, which is not shown in the illustration, should preferably be set so that it is located outside the isomagnetic field line of 5 Gauss.

[0063] Figures 2 and 3 show the rotation of bed 2 relative to magnetic structure 1, illustrating two approximate rotational positions of the bed: one where the bed and consequently the patient are located within the housing cavity of magnetic structure 1 (Figure 2), and another where the bed is located outside the outer surgical station, i.e., outside the isomagnetic field lines corresponding to a magnetic field strength of 5 Gauss (Figure 3). The rotation of bed 2 around axis V is indicated by arrow F1.

[0064] As shown in Figures 4 and 5, the bed can be supported by the column 202 by a connecting joint that allows at least one additional degree of freedom. In Figures 4 and 5, a swivel joint (rotational joint) along the horizontal axis is also provided when connecting the bed to the column 202, indicated by arrow F2 and axis O.

[0065] This can be achieved by a universal joint. One of its elements is fixed to the top of a rotary joint around the vertical axis V, and the other is fixed to the bed 2. It can also be achieved by other types of joints.

[0066] Thus, bed 2 can be swung (tilted) both upward and downward relative to its horizontal position, meaning the patient's head can be positioned higher or lower than their feet. These positions are advantageous, for example, when it is desirable to reduce blood flow to the surgical site, or when the optimal position for the surgeon is higher or lower than the position planned for moving the bed into the patient-receiving cavity of the magnetic structure.

[0067] Referring to Figure 6, we can consider an additional third degree of freedom regarding the height from the floor while maintaining the horizontal position of the bed. Of course, raising and lowering the bed 2 using this third degree of freedom can also be done in combination with the second degree of freedom which tilts the bed relative to the horizontal position.

[0068] As indicated by arrow F3, the raising and lowering of bed 2 can be achieved via an extendable column 202 having an extendable telescopic configuration.

[0069] As shown in Figures 7 and 8, it is possible to have a fourth degree of freedom that allows the surface of the bed 2 to be translated parallel to the column 202, and / or to be extended or retracted along the longitudinal direction of the bed, in lieu of or in combination with one, more, or all of the movements of the bed 2 made possible by each of the aforementioned degrees of freedom.

[0070] The position of the column 202 along the longitudinal direction of the bed can be changed, for example, by a slide that is fixed to the upper end of the column 202 and slidably engages with a guide or rail fixed to the underside of the bed.

[0071] In this case, the length of the bed remains fixed.

[0072] However, in the illustrated example, the bed consists of at least two parts, each configured to be relatively movable along the longitudinal direction of the bed, such as a telescopic configuration of bed 2 itself.

[0073] In this case, the overall length of bed 2 changes. This fourth degree of freedom is indicated by arrow F4.

[0074] As is clear, this degree of freedom allows the patient's head to be perfectly aligned with the center of imaging volume V, and furthermore, to be precisely aligned with the expected position of the patient's head at the surgical station.

[0075] The translation of the bed by F4, whether in the form of changing its position relative to column 202 or in the form of a variation that changes the length of the bed, allows the surgical station to be positioned further away from the magnetic structure, and optionally, it can be brought even closer to limit its action.

[0076] Since the relative position between the surgical station and the magnetic structure 1 depends on the strength B0 of the magnetic field generated by the magnet, it is possible to increase the distance between the surgical station and the magnetic structure to further reduce the influence of the magnetic field leaking outside the magnetic structure, or to position the surgical station to maintain it outside the magnetic field line of 5 Gauss or more, even when the strength of the static magnetic field is high.

[0077] According to a modification of the embodiment which may be provided in place of or in combination of one or more modifications relating to the second to fourth degrees of freedom, the surface of the patient-supporting bed 2 is divided into two parts. One of these, 402, is located at the bed end opposite to the end connected to the column and consists of a bed end strip on which the patient restraint device 602 is placed.

[0078] End 402 is hinged to allow rotation around a horizontal axis indicated by arrow F5, which allows the patient's head to be positioned higher than the rest of the body.

[0079] As shown in Figure 9, the head restraint device 602 is cantilevered outward from the corresponding edge of the bed, for example, via a bracket. The length of the bracket is set so that the end is at shoulder height or lower.

[0080] Movement corresponding to each degree of freedom can be controlled manually, and more preferably by motor drive. These can be electrically and / or hydraulically and / or pneumatically driven, provided in combination with a control unit, preferably programmable, and capable of controlling the bed's movement via a control interface.

[0081] To facilitate the movement of the bed between the surgical station and the imaging position, it is possible to implement commands that already include combinations of movements corresponding to two or more degrees of freedom and are executed sequentially, simultaneously, or partially simultaneously. In this case, patient positioning can be completed automatically from one position to another, and staff can manually fine-tune the patient's position as needed.

[0082] Of course, the control interface can be implemented via wired or wireless connection, including wireless connections such as Wi-Fi, Bluetooth®, or similar technologies. Furthermore, voice control interfaces and / or gesture control interfaces can also be considered.

[0083] Figures 10 and 11 show, as non-limiting examples, two possible embodiments of a receiving coil particularly suitable for intraoperative imaging, characterized by its ability to be rapidly attached to the patient's head at the surgical site.

[0084] Figure 10 shows a cross-sectional view of a craniosac along the vertical transverse plane of the bed, showing a fixing plate 100 on which an anatomical base 101 supports the patient's head. Two wings 102 and 103, each supported by a hinge 104, are provided at the lateral ends of the anatomical base 101, forming two segments of the receiving coil.

[0085] The conductors 105 constituting the coil circuit are embedded in both the anatomical base 101 and the wings 102 and 103. The conductors embedded in wings 102 and 103 are connected to the conductors embedded in base 101 via flexible connecting conductors 106. Meanwhile, the free ends of wings 102 and 103 can be fixed to each other by a detachable coupling mechanical device, schematically shown as 107, in both the closed and operating states of the coil. Furthermore, if necessary, segments of conductor 101 in the two wings can also be connected to their corresponding ends via electrical connection terminals 108.

[0086] The conductive segments of wings 102 and 103 are connected to the segments of the support base 101 at the hinge 104, for example, via flexible conductors or movable electrical couplings.

[0087] The open state of the coil, which allows access to the surgical site, is indicated by a dashed line, and similarly, the state of the flexible connection terminal 106 of the conductor segment 105 at the hinge 104 is also shown.

[0088] Alternatively, the coil may be formed from multiple plates or modules, each of which is detachably interconnected and may include conductive segments that form a receiving coil circuit. These elements can be detachably coupled to each other and to a substrate and / or a patient's head restraint device via mechanical couplings. Terminals for electrically connecting the conductive segments of the coil circuit are also provided and can be coupled and uncoupled from each other. Preferably, the mechanical coupling device and the electrical coupling device are integrated with each other, allowing the elements forming the coil to be coupled mechanically and electrically simultaneously.

[0089] Figure 11 shows coil 110 as a possible additional modification of the coil, which consists of an annular coil and can be fixed to the patient's head in various positions, for example, using a fixation strap 111. The fixation strap 111 is shaped and sized so that its opening is centered on the surgical site, so that the annular coil surrounds the surgical site while maintaining access for the surgeon.

[0090] The examples presented here are merely two non-exclusive examples, but the system according to the present invention can of course also use coils and / or rigid coils without openings. For example, it is possible to provide a rigid coil with an integrated mechanical mounting system on top of the patient support table.

[0091] The above configuration makes it possible to move patients easily and quickly between the surgical station and the magnetic resonance imaging (MRI) diagnostic device, thereby shortening the overall surgical time and contributing to safer and more comfortable MRI image acquisition.

Claims

1. A system for acquiring images using intraoperative magnetic resonance imaging, specifically for the purpose of obtaining images to confirm the progress of brain surgery, The aforementioned system, A magnetic structure that generates a static magnetic field and partitions or surrounds, on at least some sides, a containment space for accommodating at least the patient's head, A bed that can move to different relative positions with respect to the magnetic structure, Equipped with, The aforementioned position is located between an end position in which the bed is at least partially within the accommodation space and an outer end position in which the bed is outside the accommodation space and at a predetermined distance from the magnetic structure. It is a system, The magnetic structure has a horizontal U-shaped or C-shaped cross-section, The magnetic structure comprises at least one vertical connecting element connecting two horizontal wall elements that are vertically separated from each other, and the two horizontal wall elements are cantilevered by the vertical element at a predetermined distance from each other. The aforementioned vertical element is connected to the two wall elements at its side ends in a manner offset from the center. The horizontal wall element and the vertical element define a containment space for accommodating at least a portion of the patient's body in the upper, lower, and at least one vertical side. The horizontal wall element is equipped with a means for generating a static magnetic field that penetrates the containment space, The patient support bed is located outside the magnetic structure and has one end positioned at a predetermined distance from the magnetic structure. The aforementioned patient support bed is cantilevered at the opposite end by a column, The column is connected to the bed in the region of the outer end, and the patient support bed is rotatable around a vertical axis that coincides with or is parallel to the axis of the column, thereby allowing the bed to swing continuously between the two end positions. The bed can be continuously oscillated between two end positions along a predetermined angular path. The bed can be continuously oscillated between the two end positions. One of the two end positions is defined as the imaging position, where the bed end opposite the outer end provides the patient's head positioning region, the outer end is located within the patient's accommodation space of the magnetic structure, and the patient's head positioning region is positioned in the correct image acquisition position relative to the magnetic structure. In the other of the two end positions, the bed end of the patient support bed opposite to the outer end is positioned at a predetermined distance from the magnetic structure and is located at the surgical station. The system is characterized in that the oscillation angle path of the patient support bed is less than 90° and is only around the vertical rotation axis.

2. The distance of the magnetic structure from the central vertical axis is selected such that, when the bed is rotated to a position within the magnetic structure, the patient's head positioning region is positioned relative to the magnetic structure so as to coincide with the so-called imaging volume. The imaging volume is part of the total volume of the patient's containment space, which allows for the acquisition of useful and high-quality diagnostic images due to the sufficient uniformity of the static magnetic field generated by the permanent magnet. This positions the head of the patient lying on the patient support bed to coincide with the imaging volume. The aforementioned distance and the rotation angle of the bed around the vertical rotation axis are selected such that, at the outer end position, the bed end corresponding to the patient's head positioning area is positioned relative to the magnetic structure such that the influence of the static magnetic field penetrating from the magnetic structure is below a predetermined intensity value, and the bed end does not interfere with the equipment and surgical unit necessary for performing the surgery. The system according to claim 1.

3. The bed is characterized in that it can be raised and lowered vertically by a bidirectional lifting mechanism. The system according to claim 1 or 2.

4. The bed is equipped with means configured to extend and / or linearly move the bed relative to the support column, thereby making it possible to change not only the total length of the bed and / or the path of the ends of the bed, which are intended to enter the magnetic structure, but also the position of the ends of the bed corresponding to the head relative to the column, according to the user's choice. The system according to any one or more of claims 1 to 3.

5. The bed is equipped with a rotatable support joint configured to allow rotation around a substantially horizontal axis, that is, rotation from top to bottom or vice versa. The system according to any one or more of claims 1 to 4.

6. The end zone of the bed opposite to the column is comprised of an end zone hinged to swing around a horizontal axis perpendicular to the longitudinal direction of the bed, thereby enabling the end zone to swing upward and / or downward around the horizontal axis relative to the rest of the bed. The system according to any one or more of claims 1 to 5.

7. Each movement corresponding to a different degree of freedom is controllable by an electric actuator and / or a hydraulic or pneumatic actuator, or manually, and each movement can be performed at least partially simultaneously, sequentially, and / or with partially overlapping time. The system according to any one or more of claims 1 to 6.

8. The positioning device for fixing the patient's head to the bed is permanently or detachably applicable to the bed. The head position fixing or restraining device is provided in combination with an MRI signal receiving coil. The receiving coil for the MRI signal is formed by a single or multiple elements that house conductors constituting a coil circuit, or segments of conductors that are electrically connected to or can be connected to each other. The single or multiple elements are detachably attached at a predetermined position to at least a portion of the structural elements of the patient's head restraint device, and constitute a receiving coil for the head when attached to the head restraint device and when the conductor segment is connected. The system according to any one or more of claims 1 to 7.

9. Some or all of the elements constituting the receiving coil are stably hinged to the support base of the patient's head of the head restraint device or to other structural members of the restraint device, thereby the elements, and / or the support base of the patient's head, and / or other structural members of the patient's head restraint device further comprising the receiving coil circuit segments, are arranged to swing between a position in which they are mechanically and electrically close to and connected to each other to form the receiving coil, and an open position in which the segments are separated from each other to allow access to the patient's head. The system according to claim 8.

10. The receiving coil is annular in shape and includes means for fixing it to the patient's head and / or the craniosac, the means of which can be selected from a clamp band or a belt, the inner diameter and planar shape of the annular shape are configured to accommodate at least the surgical field within the opening, and the receiving coil is equipped with the patient's head to allow access to the surgical field. The system according to any one or more of claims 1 to 9.

11. The system is provided in combination with a surgical station located at a predetermined distance from the imaging system. The aforementioned station is A unit for monitoring the physiological parameters of a patient, using sensors and / or probes applied to the patient and connected to a control unit by cable. and / or, A unit for administering one or more drugs during surgery via an injector connected to the patient through a tube and needle. It has at least one of the following: The bed is provided with a removable fastener or removable restraint member for the cable and / or tube on at least a portion of its surface extension and / or peripheral edge, The cable and / or tube have redundant length and are capable of following the movement of the bed, particularly the rotation between the two end positions. The system according to any one or more of claims 1 to 10.

12. When the end position of the patient support bed, which is the position where the patient's head positioning area of ​​the patient support bed is located, coincides with the surgical position of the surgical station, the magnetic field strength transmitted from the gantry of the magnetic structure is outside the potential line of 5 Gauss of the magnetic field generated by the magnetic structure, that is, the magnetic field strength is preferably not higher than 5 Gauss, or lower than 5 Gauss. The system according to any one or more of claims 1 to 11.

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