A magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs

Abstract

The present invention belongs to the field of magnetic resonance technology, specifically a magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs, comprising: a convex lower hard structure body and a T-shaped upper soft-hard integrated structure; wherein the convex lower hard structure body comprises a bottom plate and a convex structure arranged in the middle of the upper surface of the bottom plate, the convex structure is a hollow frame with an upper opening, and baffle clamps are arranged on both sides of the upper surface of the bottom plate; the T-shaped upper soft-hard integrated structure comprises a hard structure body and two-wing flexible structures arranged on both sides of the hard structure body, and the lower surface of the hard structure body is connected with a middle combination card block; the bottom plate, the hard structure body, and the two-wing flexible structures are all provided with radio frequency circuits. The imaging efficiency of the present invention always maintains an optimal state, ensuring the performance of the signal-to-noise ratio, which means that more delicate diagnostic data can be obtained with a shorter inspection time for clinical purposes.

Description

Technical Field

[0001] The invention relates to the field of magnetic resonance technology, in particular to a magnetic resonance imaging device used for simultaneously scanning double knees, double ankles or double lower limbs. Background Art

[0002] Magnetic resonance imaging system (MRI) is an application of nuclear magnetic resonance (NMR) in medicine. The main magnetic system of the MRI system generates a uniform strong magnetic field (called the main magnetic field of the MRI system - B 0 ). The hydrogen nuclei in the human body are in B 0 Spin polarization occurs under the field. The magnetically polarized hydrogen nuclear spin generates magnetic moment i in the human body. 0 In the case of external magnetic field excitation other than 0 The direction is coaxial and does not produce useful information.

[0003] When there is an external uniform radio frequency (RF) magnetic field (called the excitation magnetic field or B 1 When a magnetic field exists, the magnetic moment in the human body is stimulated to produce nuclear magnetic resonance signals, which are collected by the receiving coil, integrated and processed by the electronic circuit and software, and finally the data and images of the magnetic resonance imaging system (MRI) are obtained.

[0004] Specifically, the RF transmitting coil generates B in the image area to be detected. 1 The RF transmitting coil is driven by a computer-controlled RF transmitter using a power amplifier. During the excitation process, the atomic nuclear spin system absorbs energy, causing the magnetic moment to precess around the main magnetic field. After excitation, the precessing magnetic moment will undergo free induction decay (FID), release the energy it absorbed and return to a steady state. The energy released during the free induction decay (FID) process propagates to the surroundings in the form of a radio frequency electromagnetic field. The receiving radio frequency coil placed near the excited part of the human body will be induced by this radio frequency electromagnetic field to generate an induced voltage, which is amplified by the preamplifier to obtain a nuclear magnetic resonance (NMR) signal. The receiving radio frequency coil can be the transmitting coil itself or an independent coil specifically for receiving radio frequency signals. The gradient coil integrated in the main magnetic field system can generate additional pulsed gradient magnetic fields to selectively excite the nuclei in the body at the required position, and perform frequency encoding and phase encoding on the signals, so as to establish a complete nuclear magnetic resonance signal map in the spatial frequency coordinate system (k space), and finally obtain a complete magnetic resonance image in the ordinary space (R space) after Fourier transformation.

[0005] For the scenario of bilateral limb injury at the same time, the main types are: soft tissue injury, which is a common type of lower limb training injury among soldiers, mainly including muscle strain, ligament tear, etc. This type of injury is usually caused by overuse or improper posture; bone injury: bone injury also accounts for a certain proportion of lower limb training injuries, mainly including fractures, bone cracks, etc. This type of injury is often caused by external impact or long-term stress accumulation. The main reasons for the occurrence of these situations are: excessive intensity of sports training, long-term high-intensity training such as running and jumping can easily lead to fatigue of lower limb muscles and bones, and then cause injuries; irregular sports movements: incorrect sports postures or movement patterns increase the risk of lower limb injuries. For example, when running, the toes land too heavily and the knees buckle inward; poor training venues: uneven, hard or soft ground may have adverse effects on the lower limbs. Uneven ground can easily lead to falls and sprains, while hard ground may increase the burden on bones and joints. The characteristics of this type of injury are: 1. Various types of injuries, including acute traumatic injuries and overwork injuries. The incidence of acute traumatic injuries in the knee, ankle, and ligaments is significantly higher than that in overuse injuries, but the incidence in the hip, foot, and bones is significantly lower than that in overuse injuries; 2. Concentrated injury sites: mainly occur in the knee, ankle, and calf, among which the knee is the most common injury site; 3. Complex injury structures: joints, ligaments, and bones may all be injured, among which the meniscus, anterior cruciate ligament, and femur are the main injury structures of joints, ligaments, and bones respectively; 4. It is especially common in the military or professional athletes, mainly in men: men account for the vast majority of injured patients, and the incidence is highest in young patients (21-30 years old); 5. Simultaneous injuries to multiple parts are also relatively common, and there is a certain probability that both sides will be injured at the same time.

[0006] As an advanced imaging examination technology, magnetic resonance imaging (MRI) can clearly display the structures of lower limb soft tissues, bones, blood vessels and nerves for lower limb bone and joint injuries. The detailed injury information can help doctors accurately diagnose and formulate targeted treatment plans. Specifically, at the level of soft tissue injury, MRI can clearly display the morphology and signal changes of soft tissues such as muscles, ligaments, and tendons, which is helpful for diagnosing soft tissue injuries such as muscle strains and ligament tears; at the level of bone injury: MRI is also of great significance for the diagnosis of bone injuries such as fractures and bone cracks. It can show the location and morphology of the fracture line and the damage to the surrounding soft tissues. For example, stress fractures may appear as local cortical thickening, periosteal hyperplasia and other changes in MRI. For knee and ankle joint injuries: MRI can observe the intra-articular structures in detail, such as meniscus, ligaments, articular cartilage, etc., which is helpful for diagnosing joint injuries such as joint sprains and dislocations; furthermore, for vascular and nerve injuries: MRI can also display the vascular and nerve structures of the lower limbs, which is helpful for diagnosing vascular stenosis, occlusion and nerve injury.

[0007] At present, the main methods and modes used in the field of magnetic resonance imaging for lower limb examinations are:

[0008] Knee

[0009] At present, the main methods for MRI examination of the knee joint are: 1. Use a dedicated knee joint coil to fix and cover the unilateral knee joint, and then complete the examination. The dedicated knee joint coil is usually cylindrical, hollow inside to accommodate the patient's knee joint, and the coverage range in the head-to-foot direction is usually 160mm-180mm, with 8 to 16 receiving units. This high-density array layout ensures that it can obtain a higher imaging signal-to-noise ratio and obtain higher-quality imaging in a shorter examination time. However, this structure relies on its fixed shape, that is, it accommodates the patient's knee joint. The imaging field of view is fixed and immutable. Therefore, when facing parts of the same shape but different sizes (thighs, calves), there will be certain limitations. For example, the thigh is generally thicker and has a larger diameter, so the fixed space may not be able to accommodate its positioning and imaging; the calf is generally thinner, so the filling rate is low after it is placed in the coil, so the acquisition efficiency of the RF coil will be greatly attenuated, and the optimal imaging results cannot be obtained; on the other hand, for the ankle, because the sole and calf are L-shaped, it is almost impossible to use the knee joint coil for examination.

[0010] 2. Use a flexible multifunctional coil to wrap and scan the unilateral part. The biggest advantage of the flexible coil is that it can completely wrap the target part. In this way, it will hardly attenuate the radio frequency field, and the acquisition efficiency is extremely high, which can basically fully guarantee the performance of the coil. However, on different magnetic resonance platforms, its configuration is different, ranging from 4 to 16 channels, so the imaging performance will vary greatly. Moreover, since it is a multifunctional coil, its main design goal is to cope with different scenarios, so its accessories are relatively simple, lacking a relative framework and fixed facilities, and cannot effectively constrain the detection part. In magnetic resonance examination, there is a big taboo, that is, during the implementation of the examination, the part to be detected needs to be completely still. For this reason, although the flexible multifunctional coil has a higher receiving efficiency, it is easily affected by the patient's movement in the scenario of examining injured patients, resulting in various artifacts and interference with diagnostic images. Similarly, it is only suitable for unilateral examination.

[0011] Legs (thigh or calf)

[0012] The legs here refer to the use of an abdominal coil to cover the patient's bilateral lower limbs. The advantage of this mode is that the positioning is simple. The abdominal coil with a large field of view is directly covered on the patient's bilateral lower limbs, and it can be combined with the inherent lower coil array of the system bed. There is no need for precise positioning. It forms a larger imaging range, enough to include bilateral thighs including knee joints or bilateral calves including knee joints or bilateral calves including ankle joints. However, magnetic resonance imaging has a basic physical property, that is, the more channels are focused in the targeted area of ​​interest, the higher the signal-to-noise ratio can be obtained, and the improvement of the signal-to-noise ratio, or the overflow of performance, can ensure that it is converted into a more delicate scanning resolution while meeting the diagnostic imaging quality, that is, it can display smaller lesions. Then, the disadvantage of using abdominal coil for scanning is reflected. Since it is designed mainly for comprehensive examination of substantial organs in the trunk, a larger imaging field of view is adopted in medical diagnosis requirements. For joint and bone parts, medical diagnosis requires clearer display of details of small structures such as cartilage and ligaments. The coverage of effective channels of such parts by abdominal coil is only half or one quarter of the configured channels. For example, when a 16-channel or 32-channel abdominal imaging array is used to examine the knee joint, only 8 or 4 receiving arrays can truly target and cover the knee joint, and the rest of the configuration has no contribution to the targeted part. Therefore, although this solution can provide a global display, it is still very lacking at the microscopic level.

[0013] Ankle

[0014] The usage of the ankle joint is similar to that of the knee joint, and can also be scanned with dedicated or multi-function coils, and the results obtained are also similar. The imaging quality of the dedicated coil is guaranteed, but it can only meet the needs of the ankle joint and cannot meet the needs of bilateral examinations. The configuration of the multi-function coil is uneven, which is greatly affected by the patient's cooperation, and it is also difficult to operate when wrapping the L-shaped ankle.

[0015] Bilateral knee joints At present, some scientific research institutes have also seen solutions that can accommodate bilateral knee joints for imaging. This prototype uses a structure similar to two cylindrical knee joint coils spliced ​​together, in the shape of an 8, but the two cylindrical spaces are connected in the middle and their diameters are fixed. For standard knee joints, this may be a more reasonable solution, but considering the application of this equipment in the scenario of lower limb training injuries of military officers and soldiers, it is rather cramped. First, its imaging space is solidified and is only suitable for knee joint imaging. Furthermore, it may also be used for examination of the calf area, but not for the thigh or ankle joint; secondly, the physical fitness of military officers and soldiers is relatively strong, so its conventional size may be inappropriate for a certain proportion of officers and soldiers; thirdly, training injuries are usually accompanied by swelling or temporary fixation devices, which further limits the audience of the equipment, so this solution is not the preferred choice for training injuries of officers and soldiers. Summary of the invention

[0016] In order to solve the problem that the existing magnetic resonance imaging cannot fully and clearly display the parallel imaging of both limbs in one examination in the scenario of bilateral lower limb injuries, and can accurately display the subtle anatomical structure, pathological conditions, and signal differences; and cannot quickly conduct continuous examination and diagnosis of different parts of a group of patients of the same type without changing the examination equipment, such as thighs, knees, calves, and ankles, the purpose of the present invention is to provide a lower limb training injury imaging device that can cover bilateral limb joints, cope with thighs, knees, calves, ankles and other parts, can moderately and flexibly change the coverage area and coverage shape, can adapt to most local conditions of lower limbs, cope with officers, soldiers, and athletes of different heights, weights, and body shapes, and has a high-density signal acquisition matrix to ensure long-term continuous operation. In this way, compared with the existing imaging schemes, whether in terms of the convenience of examination, the quality of imaging, or the efficiency of examination circulation, a relatively high level of balance can be achieved, so as to establish a new evaluation system for doctors' diagnosis and treatment in specific scenarios.

[0017] To achieve the above object, the present invention provides the following technical solution: a magnetic resonance imaging device for simultaneous scanning of two knees, two ankles or two lower limbs, comprising:

[0018] Convex lower hard structure main body and T-shaped upper soft and hard integrated structure;

[0019] The convex lower hard structure body includes a bottom plate and a convex structure arranged in the middle of the upper surface of the bottom plate, the convex structure is a hollow frame with an upper opening, and baffle clamps are arranged on both sides of the upper surface of the bottom plate;

[0020] The T-shaped upper soft-hard integrated structure includes an upper hard structure plate and two wing flexible structures arranged on both sides of the upper hard structure plate, the lower surface of the upper hard structure plate is connected to a middle combination card block, and the interior of the middle combination card block is connected to a shape adapter matching the middle combination card block;

[0021] The bottom plate, the upper hard structure plate, and the two wing flexible structures are all provided with radio frequency circuits;

[0022] Both ends of the baffle clamp are provided with slide blocks, and both ends of the bottom plate are provided with guide rails matching the slide blocks on the front and rear sides;

[0023] A groove is provided on the lower front side of the form adapter, an axial hole is connected to the rear side of the outer wall of the form adapter, a rotating shaft matching the axial hole is inserted on the rear side of the outer wall of the convex structure, an angle positioning groove is provided on the front lower side of the side wall of the convex structure, and a plurality of slots are provided on the angle positioning groove, an angle positioning module is rotatably connected to the lower side of the groove of the form adapter through a pin shaft, a positioning shaft is connected to the end of the angle positioning module away from the pin shaft, and the positioning shaft matches the slot position of the angle positioning groove.

[0024] Preferably, a spiral lock is threadedly connected to the lower portion of the outer side wall of the baffle clamp, and the bottom end of the spiral lock is in contact with the upper surface of the bottom plate.

[0025] Preferably, a lifting handle is provided on the upper surface of the upper rigid structure plate.

[0026] Preferably, the thickness of the two-wing flexible structure is ≤4 mm.

[0027] Preferably, a plurality of openings are provided on the surface of the two-wing flexible structure.

[0028] Preferably, a hard protruding structure frame is provided on the surface of the two-wing flexible structure, a low-noise signal amplifier and an active detuning module are integrated on the radio frequency circuit, and the low-noise signal amplifier and the active detuning module on the T-shaped upper hard-soft integrated structure are located within the hard protruding structure frame.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The lower hard structure has a large load-bearing capacity and is mainly used to bear the patient's legs, knees and ankles. The clamps on both sides can constrain the shape of the examination area and force it to remain basically still and fixed during the entire examination process. At the same time, the high-density imaging array below can form a high-efficiency signal acquisition area behind the legs, knees and ankles. Since the rear of the legs, knees and ankles is directly placed on the lower hard structure and closely attached to it, except for the wall thickness of the structure, it is almost equivalent to being attached to the imaging array. Therefore, there is basically no attenuation loss in the acquisition of proton signals. The integrated structural body covers the upper part of the legs, knees and ankles, and the flexible structural bodies on both sides droop naturally. They can be fixed in place by using clamps on both sides and wrapped around the outside of the patient's lower limbs to form a nearly closed B1 field with the imaging array below. The filling rate in the field is close to 100%. In this way, no matter what scenario is being dealt with, the imaging efficiency of the present invention always maintains an optimal state, ensuring the performance of the signal-to-noise ratio. In clinical terms, more detailed diagnostic data can be obtained with a shorter inspection time, providing a guarantee for rapid and efficient batch inspections of training injuries, benefiting officers and soldiers. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0032] Figure 2 It is a schematic diagram of the convex lower hard structure main body of the present invention.

[0033] Figure 3 It is a schematic diagram of the positional relationship between the morphological adapter and the convex lower hard structure body of the present invention.

[0034] Figure 4 It is a schematic diagram of the main body of the T-shaped upper soft-hard integrated structure of the present invention.

[0035] Figure 5 is a schematic diagram of the double knee examination mode.

[0036] Figure 6 It is a schematic diagram of the examination mode of both lower limbs.

[0037] Figure 7 is a schematic diagram of the double ankle examination mode.

[0038] In the figure: 1. bottom plate; 2. convex structure; 3. upper hard structural plate; 4. two-wing flexible structure; 5. baffle clamp; 6. slider; 7. guide rail; 8. spiral lock; 9. lifting handle; 10. hard raised structural frame; 11. opening; 12. middle combination block; 13. shape adapter; 14. shaft hole; 15. rotating shaft; 16. angle positioning module; 17. positioning shaft; 18. angle positioning groove. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0041] Embodiment 1:

[0042] See also Figure 1-Figure 7 , the present invention provides a technical solution:

[0043] A magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs, comprising a convex lower hard structure body for carrying and accommodating the lower limbs of the human body and covering the rear area of ​​the lower limbs to collect hydrogen proton relaxation signals; and a T-shaped upper soft-hard integrated structure for covering the front area of ​​the lower limbs to collect hydrogen proton relaxation signals. The two parts can be separated up and down, which makes it easier for patients to get in and out of bed and place the lesion. The two parts are then connected for signal collection to obtain uniform, complete, and high-resolution imaging data.

[0044] The convex lower hard structure body and the T-shaped upper hard-soft integrated structure body are connected and combined through the middle morphological adapter 13. According to different positioning methods, an I-shaped pattern parallel to each other can be formed to cover and image the legs, knees and other parts. The positioning function of the morphological adapter can also be used to change an angle between the upper hard-soft integrated structure and the lower hard structure body, so as to match and cover the L-shaped ankle joint.

[0045] The integrated I-shaped structure has a hollow interior of the convex structure 2 of the lower hard structure body for nesting the shape adapter 13 , and the middle combination block 12 of the T-shaped upper soft-hard integrated structure body is connected to the lower hard structure body through the shape adapter 13 .

[0046] The integrated convex structure 2 is hollow inside and has an angle positioning groove 18 at the bottom. The angle positioning groove 18 does not work in the leg-knee mode and can be ignored. In the ankle mode, the operator can match the angle positioning groove 18 with the angle positioning module 16 and the positioning axis 17 of the morphological adapter 13 to form different angles to adjust, support and cover the ankle.

[0047] Guide rails 7 are provided on both sides of the bottom of the lower hard structure body in the head and foot directions, which are used to change and adjust the positions of the baffle clamps 5 on the left and right sides of the bottom and to fix them.

[0048] The baffle clamps 5 on both sides of the bottom left and right directions of the lower hard structure body can slide along the direction of the guide rails 7 on both sides, and are fixed by spiral locks 8 after sliding, so as to restrain the patient's legs, knees, ankles and other parts to ensure that they are fixed inwardly. At the same time, the upper two-wing flexible structures can also be constrained to be close to the patient's body, so as to fully guarantee the collection efficiency.

[0049] When the convex lower hard structure body and the T-shaped upper soft-hard integrated structure body are connected and combined, the middle combination block 12 is embedded in the shape adapter 13. According to the different body shapes of the patients, relying on gravity, the height of the upper and lower accommodation spaces is movable and variable.

[0050] The integrated I-shaped structure, the convex lower hard structure body and the T-shaped upper soft-hard integrated structure body are connected and combined. If it is necessary to adapt to the ankle, the angle positioning module 16 at the bottom of the shape adapter 13 and the lower angle positioning groove 18 are matched to obtain the expected angle, and then the T-shaped upper soft-hard integrated structure body is embedded in the shape adapter 13.

[0051] The interior of the convex lower hard structure body is provided with a radio frequency circuit. The density of the receiving unit array directly affects the imaging signal-to-noise ratio in the coverage area. The lower part of the present invention has at least 16 groups of receiving unit arrays, and each group of receiving unit arrays has an independent low-noise signal amplifier.

[0052] The T-shaped upper part is a soft-hard integrated structural body, the middle part of which is an upper hard structural plate 3, and there is a lifting handle 9 on the top to facilitate the operator to carry and place it, and the two wings are ultra-thin and ultra-flexible structural bodies (i.e., two-wing flexible structures 4), which can be curled at a large angle. In this way, during the actual scanning and inspection process, it can be wrapped around the human body and fixed by the baffle clamp 5, so as to achieve the optimization of the collection efficiency.

[0053] The solid structure below the middle of the T-shaped upper soft-hard integrated structure is a middle combined card block 12, which can be embedded in the morphological adapter 13 and used in conjunction with the lower part to ensure the symmetry of the upper and lower imaging intervals.

[0054] The middle combination block 12 of the T-shaped upper soft-hard integrated structure body is used to combine with the hollow interior of the shape adapter 13, and then match the angle positioning module 16 provided below the shape adapter 13 with the lower angle positioning groove 18 to form an I-shaped accommodating space or an accommodating space with an angle, and then perform scanning inspection.

[0055] The ultra-thin and ultra-flexible structural body of the two wings is an integrated hot-pressed lamination molding packaging frame. There are no gaps on the packaging surface. It has waterproof and dustproof properties and can be freely curled according to the user's will, with a curling angle greater than 90°.

[0056] The two-wing ultra-thin and ultra-flexible structural body is an integrated hot-pressed lamination molding packaging frame with multiple openings 11 on the surface. When the doctor positions the patient, he can confirm through the openings 11 whether the examination part is in the center of the device and whether its angle meets the diagnostic requirements. It can also ensure that heat is more easily dissipated during high SAR sequence scanning.

[0057] The ultra-thin and ultra-flexible structural body has a plurality of hard protruding structural frames 10 inside its packaging surface. The low-noise signal amplifier and active detuning module required for the receiving unit array are arranged inside the structural frame. The function of the active circuit is to control the switching state of the device according to the operating state of the system.

[0058] The ultra-thin and ultra-flexible structural body, except for x hard raised structural frames, the thickness of the flexible medium in the remaining parts does not exceed 4 mm. This can ensure the flexibility of the equipment to the greatest extent and ensure that it can wrap the patient's examination area at a large angle in various scenarios.

[0059] The T-shaped upper hard-soft integrated structural body, the hard structural body and the ultra-thin ultra-flexible structural body of the T-shaped upper hard-soft integrated structural body are both provided with radio frequency circuits. The density of the receiving unit array directly affects the imaging signal-to-noise ratio in the coverage area. The upper part of the present invention has at least 16 groups of receiving unit arrays, and each group of receiving unit arrays has an independent low-noise signal amplifier, which is in a corresponding relationship with the unit array at the lower part.

[0060] Magnetic resonance imaging of bone and joint parts has several elements: First, bone and joint lesions are common in ligaments or cartilages, which have complex and delicate structures. Therefore, a large FOV (imaging field of view) is not required to observe this information clearly. The key is to detect local signal abnormalities in these subtle structures, which requires imaging with a high spatial resolution. For 2D imaging, the scanning voxel is generally required to be within 0.6*0.6*3mm, and for 3D imaging sequences, the scanning voxel is generally required to be within 0.7*0.7*0.7mm; secondly, high-resolution scanning requires the support of a high signal-to-noise ratio. If the signal cannot be effectively highlighted and the background cannot be distinguished, the image quality will be poor. If the image is not smooth, no matter how high the resolution is, it will be meaningless. Furthermore, there is another necessary condition for scanning fine structures with high resolution, that is, the part being tested needs to remain still during the continuous inspection. Otherwise, even a small displacement will produce large artifacts for voxels of a few tenths of a millimeter, blurring the image and interfering with the diagnosis. On the other hand, for simultaneous scanning of bilateral limbs, although the coverage range in the axial field of view is consistent with the conventional mode, the coverage range in the left and right directions must be more than doubled compared with the conventional mode. Under the premise that the scanning voxels need to be guaranteed, the improvement of the imaging field of view means an increase in the signal acquisition step, that is, an increase in the scanning time. The logical essence of magnetic resonance scanning is to balance imaging resolution, imaging signal-to-noise ratio and imaging time. Generally speaking, only two of the three can be selected, that is, high-resolution and high-signal-to-noise ratio imaging requires a long time to maintain, high-signal-to-noise ratio rapid scanning requires sacrificing resolution, and high-resolution rapid scanning will reduce the imaging signal-to-noise ratio. Although this situation has improved with the continuous iteration of new technologies such as AI, algorithms, and compressed sensing, its underlying physical essence cannot be violated. The architecture of the present invention utilizes the configuration redundancy of the current mainstream magnetic resonance system to optimize the layout of the radio frequency field when the imaging field of view must be expanded, thereby achieving a new scenario of one-time scanning and inspection of both limbs while maintaining the original imaging resolution, not reducing the imaging signal-to-noise ratio, and slightly adjusting the scanning time. At the same time, this mode is not only limited to regular cylindrical limb structures, such as knee joints, thighs and calves, but is also suitable for L-shaped ankle joint structures. It truly achieves an effective fusion of precise targeting and multi-functions, subverts traditional inspection modes, and lays a high-quality data foundation for new diagnosis and treatment modes.

[0061] In the specific implementation stage, first, the convex lower hard structure body is placed on the MRI examination bed. It is made of hard plastic with no proton signal, has a large load-bearing capacity and is not easy to deform. Then, the patient is asked to sit on the examination bed, and the left and right lower limbs to be examined are placed on both sides of the middle convex structure respectively, and the patient can lie flat on his back; the clinical operator inserts the combination block in the middle of the T-shaped upper soft and hard integrated structure body into the morphological adapter in the middle of the lower hard structure body by pulling the handle. Because the morphological adapter is hollow inside, after being embedded, when encountering a patient with a relatively strong body, his thigh itself becomes the load-bearing body of the T-shaped upper soft and hard integrated structure body, making it The imaging interval is fixed; when encountering a relatively thin patient or performing a calf examination, the T-shaped upper soft-hard integrated structure body can be embedded to the bottom, but affected by the height of the combined card block, it will ensure that the upper and lower parts maintain a minimum relative distance. The advantage of this setting is that each receiving unit in the high-density imaging array is at the same operating frequency, and the upper and lower coverage areas of the RF architecture of the present invention correspond. If the distance between the upper and lower parts is too close, it will cause strong co-frequency coupling, thereby generating noise and reducing the imaging signal-to-noise ratio. Effective isolation can not only ensure that the RF field in the coverage area is uniformly controlled to attenuate, but also reduce the introduction of noise, thereby ensuring imaging quality. The two wings of the T-shaped upper soft-hard integrated structural body are ultra-thin and ultra-flexible structural bodies that are integrated with hot-pressed lamination molding and packaging. It can be curled at a large angle. After the upper part is embedded in the morphological adapter, the two wings can be wrapped around the patient's examination part, and then the baffle clamps on both sides are used to squeeze the two wings wrapped around the patient's part and the part to be examined inward together. In this way, it can not only ensure that the flexible wings can be completely close to the examination part to maximize the efficiency of signal acquisition, but also physically restrain the involuntary movement of the patient's part, greatly reducing the generation of motion artifacts. On the other hand, when performing coronal examination and scanning, squeezing and fixing the limbs on both sides inward actually reduces the imaging field of view of the area of ​​interest. When the scanning voxel remains unchanged, it means that the phase step can be reduced, which can ensure that the signal-to-noise ratio remains unchanged. The time required for acquisition is correspondingly reduced, reducing the risk of involuntary movement caused by excessive scanning time.The convex lower hard structure body and the T-shaped upper hard-soft integrated structure are both equipped with equal-weighted receiving unit arrays, with no less than 16 groups on one side. The lower array is set in the hard structure body and is laid flat, and the upper array is laid in the hard-soft integrated structure. The two wings can be deformed, curled, and wrapped with the flexible structure body. Therefore, in most application scenarios, the imaging field of view of the lower array in the left and right directions is larger than that of the upper one. The purpose of this setting is that based on the different body shapes or parts of different patients, the upper flexible wings may not wrap the outer sides sufficiently, and there may be gaps. Generally speaking, the area beyond the array The covered area cannot effectively obtain signals, but according to the characteristics of magnetic field distribution, the signal along the B1 field direction gradually decays with distance, and the signals on both sides of the B1 field are extremely attenuated. Therefore, the B1 field formed by the upper radio frequency array gradually changes from the up and down direction directly above to the left and right directions on both sides. Therefore, for it, the places where the outer limbs are not completely wrapped belong to the two sides of the B1 field, and the contribution it can make is negligible. The B1 field formed by the lower radio frequency array is always in the up and down direction, so it can effectively compensate for the shortcomings of the upper side, thereby ensuring uniform and efficient signal acquisition at the global level. Therefore, compared with previous models, the high-density deformable framework adopted by the present invention has achieved a leap in the increase of imaging field of view by more than 1 times, diversification of application scenarios, and improvement of local imaging quality instead of reduction.

[0062] like Figure 4As shown, it is a schematic diagram of the T-shaped upper soft-hard integrated structure of the present invention. The whole middle part adopts a hard structure body, and the upper part is provided with a lifting handle, which is convenient for clinical workers to carry and place. The two wings adopt an integrated hot pressing film packaging process as the frame body. There are no other structural parts or fixing parts on the packaging surface, such as screw holes, etc., which is a complete body. There are multiple hard protruding structural frames inside the packaging surface, and the height does not exceed 10mm. A low-noise signal amplifier and an active detuning module are arranged inside the structural frame. The low-noise signal amplifier amplifies the microvolt-level signal obtained by the receiving unit in the first stage in the receiving state and transmits it to the magnetic resonance system through a communication cable; the active detuning module is controlled by the system and switches the working mode of the imaging array when the system is excited and received. There are multiple open space openings on the packaging surface that run through from top to bottom. Because the continuous scanning and examination of magnetic resonance will accumulate SAR values, the increase of SAR will cause the human body to heat up. The open structure can allow the patient to be in a state of ventilation and heat dissipation as much as possible during the scanning process. Except for multiple rigid raised structural frames, the average thickness of the flexible medium in the rest of the parts does not exceed 4 mm, so the flexible wings can be greatly curled to adapt to different parts and different body shapes. A solid combination card block is provided on the lower middle side of the rigid structure body. During use, the clinician places the patient's part to be examined on both sides of the lower rigid structure body, and then inserts the combination card block into the morphological adapter in the middle to complete the coverage of the equipment. The functions of the card block are: 1. Ensure the alignment of the upper and lower imaging arrays to ensure the integrity of the radio frequency field; 2. Ensure that the upper array will not be displaced in the head and feet, left and right directions during the examination; 3. Ensure that the upper imaging array can fit according to the patient's body shape and up and down movements, while not causing coupling noise due to the close distance.

[0063] like Figure 2The figure shows a schematic diagram of the convex lower hard structure of the present invention, which has a mountain-shaped overall appearance, and a receiving unit array is laid inside the bottom plane, which is also equipped with a low-noise signal amplifier and an active detuning module, and the working mode is the same as the upper part. The convex structure in the middle is hollow inside, and a morphological adapter is nested therein. A plurality of angle positioning grooves are provided on one side of the bottom of the convex structure in the middle, and both ends of the positioning grooves are penetrated. Clinical workers can manually embed the angle positioning modules under the morphological adapter into different grooves, and can set the morphological adapter and the lower structure body to several different angles. Then, the upper soft-hard integrated structure of the morphological adapter and the internal imaging array form a corresponding angle with the lower structure body, and the scanning of the bilateral ankle joints can be completed in the coverage mode with the angle. The two sides of the convex lower hard structure body are baffle clamps, and the front and rear sides of the clamps can be embedded in the guide rails on both sides of the head and feet direction of the hard structure body, and can slide along the guide rails to change its relative position with the middle convex structure. In actual use, the patient places both lower limbs on both sides of the lower hard structure body, and then covers and wraps the T-shaped upper part, and then pushes the baffle clamps on both sides to the middle along the guide rails, so that the side limbs are close to the middle convex structure, and the flexible wings are close to the bilateral limbs, and then the spiral locks on the outside of the baffle clamps are tightened and fixed. In this way, firstly, the patient's bilateral limbs are fixed and will not move. Secondly, the left and right limbs are brought together to the middle, which can reduce the imaging field of view in the left and right directions, reduce the acquisition steps, compress the imaging time, and the flexible wings are completely in fit with the measured limbs to achieve the most efficient signal acquisition.

[0064] like Figure 3The figure shows a schematic diagram of the positional relationship between the morphological adapter and the convex lower hard structure body of the present invention. The morphological adapter is roughly rectangular, and an angle positioning module is provided at the bottom. The module can freely change the angle between 0 and 180 degrees. Under normal circumstances, the module can be completely laid flat and present a rectangular shape with the morphological adapter. At the same time, the outer specifications of the morphological adapter are set according to the inner dimensions of the convex structure in the middle of the convex lower hard structure body, which is slightly smaller and can be completely embedded therein, while the inner side of the morphological adapter is hollow, and the specifications match the combination card block in the middle of the T-shaped upper soft-hard integrated structure body, which is slightly larger and can be completely embedded therein. As a transitional adapter component, when conducting normal inspections of the bilateral legs and knees, the morphology adapter does not need to be taken out. It is only necessary to lay its angle positioning module flat and embed the entire device in the lower hard structure body. The T-shaped upper portion is directly inserted therein, so that the present invention presents an I-shaped structure to complete the scan. However, when conducting an ankle joint inspection, the ankle is L-shaped, and the I-shaped structural space cannot be properly covered. At this time, the morphology adapter needs to be taken out, and the angle positioning module at the bottom thereof is adjusted to an angle that matches the lower angle positioning groove, so that the entire morphology adapter and the lower hard structure body form a placement mode with an angle, and then the T-shaped upper portion is embedded in the morphology adapter, so that the entire imaging range can be transformed into a shape with a high back and a low front. In this way, the entire ankle joint and even the sole of the foot can be covered to complete the inspection of both sides of the foot.

[0065] like Figure 5 Figure 6 Figure 7 The figure shows a schematic diagram of the use and coverage of the present invention on different areas of the bilateral lower limbs, which fully demonstrates the wide applicability and superiority of the present invention.

[0066] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure marks in the claims should not be regarded as limiting the claims involved.

[0067] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs, characterized in that: include: Convex lower hard structure main body and T-shaped upper soft and hard integrated structure; The convex lower hard structure body comprises a bottom plate (1) and a convex structure (2) arranged in the middle of the upper surface of the bottom plate (1); the convex structure (2) is in the shape of a hollow frame with an open top; baffle clamps (5) are arranged on both sides of the upper surface of the bottom plate (1); The T-shaped upper soft-hard integrated structure comprises an upper hard structure plate (3) and two wing flexible structures (4) arranged on both sides of the upper hard structure plate (3); the lower surface of the upper hard structure plate (3) is connected to a middle combination card block (12); and the interior of the middle combination card block is connected to a shape adapter (13) matching the middle combination card block (12); The base plate (1), the upper hard structure plate (3), and the two-wing flexible structures (4) are all provided with radio frequency circuits; Both ends of the baffle clamp (5) are provided with sliders (6), and both ends and front and rear sides of the bottom plate (1) are provided with guide rails (7) matching the sliders (6); A groove is provided on the lower front side of the form adapter (13); an axial hole (14) is connected to the rear side of the outer wall of the form adapter (13); a rotating shaft (15) matching the axial hole (14) is inserted into the rear side of the outer wall of the convex structure (2); an angle positioning groove (18) is provided on the lower front side of the side wall of the convex structure (2); a plurality of slots are provided on the angle positioning groove (18); an angle positioning module (16) is rotatably connected to the lower side of the groove of the form adapter (13) via a pin shaft; a positioning shaft (17) is connected to the end of the angle positioning module (16) away from the pin shaft; the positioning shaft (17) matches the slot of the angle positioning groove (18).

2. A magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs according to claim 1, characterized in that: A spiral lock buckle (8) is threadedly connected to the lower portion of the outer side wall of the baffle clamp (5), and the bottom end of the spiral lock buckle (8) is in contact with the upper surface of the bottom plate (1).

3. A magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs according to claim 1, characterized in that: The upper surface of the upper rigid structure plate (3) is provided with a lifting handle (9).

4. A magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs according to claim 1, characterized in that: The thickness of the two-wing flexible structure (4) is ≤4 mm.

5. The magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs according to claim 1, characterized in that: A plurality of openings (11) are provided on the surface of the two-wing flexible structure (4).

6. The magnetic resonance imaging device for simultaneous scanning of both knees, both ankles or both lower limbs according to claim 1, characterized in that: A hard protruding structure frame (10) is provided on the surface of the two-wing flexible structure (4); a low-noise signal amplifier and an active detuning module are integrated on the radio frequency circuit; and the low-noise signal amplifier and the active detuning module on the T-shaped upper soft-hard integrated structure are located inside the hard protruding structure frame (10).

Images