阅读说明：本技术 一种腔内磁共振射频线圈及其使用方法 (Intracavity magnetic resonance radio frequency coil and use method thereof ) 是由 杨春升 郑利敏 宋长明 程东旭 于 2020-05-21 设计创作，主要内容包括：本发明提出了一种腔内磁共振射频线圈及其使用方法,腔内磁共振射频线圈包括用于载入目标腔体的气囊,气囊内设置有腔内线圈,腔内线圈包括表面线圈组件和激励线圈,表面线圈组件设置于气囊的内表面,用于目标区域组织的磁共振信号的激励与采集,激励线圈设置于气囊内且与表面线圈配合,用于提供激励耦合或接收来自目标区域组织的磁共振信号。本发明方便装载入患者体内,减少患者的不适感,最大程度提高检测灵敏度,防止表面线圈组件中电路板线路拉断,有效减小SAR值。(The invention provides an intracavity magnetic resonance radio frequency coil and a using method thereof, wherein the intracavity magnetic resonance radio frequency coil comprises an air bag loaded into a target cavity, the air bag is internally provided with an intracavity coil, the intracavity coil comprises a surface coil component and an exciting coil, the surface coil component is arranged on the inner surface of the air bag and is used for exciting and acquiring magnetic resonance signals of tissues of a target region, and the exciting coil is arranged in the air bag and is matched with the surface coil and is used for providing excitation coupling or receiving the magnetic resonance signals from the tissues of the target region. The invention is convenient to load in the body of a patient, reduces the uncomfortable feeling of the patient, improves the detection sensitivity to the maximum extent, prevents the circuit board line in the surface coil component from being broken, and effectively reduces the SAR value.)

1. An intracavity magnetic resonance radio frequency coil, characterized by: the magnetic resonance imaging device comprises an air bag (1) used for being loaded into a target cavity, wherein an intracavity coil is arranged in the air bag (1), the intracavity coil comprises a surface coil assembly and an excitation coil (2), the surface coil assembly is arranged on the inner surface of the air bag (1) and used for exciting and collecting magnetic resonance signals of tissues of a target region, and the excitation coil (2) is arranged in the air bag (1) and matched with the surface coil and used for providing excitation coupling or receiving the magnetic resonance signals from the tissues of the target region.

2. An intracavity magnetic resonance radio frequency coil as claimed in claim 1 wherein: the surface coil assembly comprises an upper surface coil (3) arranged on the inner upper surface of the air bag (1) and a lower surface coil (4) arranged on the inner lower surface of the air bag (1), an exciting coil (2) is arranged in the air bag (1) between the upper surface coil (3) and the lower surface coil (4), and the distance between the exciting coil (2) and the upper surface coil (3) and the distance between the exciting coil (2) and the lower surface coil (4) are adjusted by adjusting the inflating quantity of the air bag (1).

3. An intracavity magnetic resonance radio frequency coil as claimed in claim 1 or claim 2 wherein: the upper surface and the lower surface of the air bag (1) are both made of non-telescopic materials and have flexibility, the side wall of the air bag (1) between the upper surface and the lower surface is made of elastic telescopic materials, and the surface coil assembly is an annular coil made of a flexible circuit board.

4. An intracavity magnetic resonance radio frequency coil as claimed in claim 1 or claim 2 wherein: the exciting coil (2) comprises a coupling ring, one end of the coupling ring is arranged in the air bag (1), the other end of the coupling ring is connected with an internal coaxial cable (5) arranged in the air bag (1), the internal coaxial cable (5) is connected with a radio frequency connector (6) on the surface of the air bag (1), and the internal coaxial cable (5) is connected with the air bag (1) through a sealing ring (7).

5. An intracavity magnetic resonance radio frequency coil as claimed in claim 4 wherein: the gas-liquid separation device is characterized by further comprising an inner connecting assembly and an outer connecting assembly, wherein the inner connecting assembly and the outer connecting assembly comprise a gas pipe (8) connected with the gas bag (1), an external coaxial cable (9) connected with the radio frequency connector (6) and a flexible sleeve (10) wrapped on the outer sides of the gas bag (1) and the external coaxial cable (9), and the external coaxial cable (9) is connected with the magnetic resonance spectrometer system.

6. An intracavity magnetic resonance radio frequency coil as claimed in claim 3 wherein: the non-telescopic material is polytetrafluoroethylene plastic, and the elastic telescopic material is butadiene-acrylonitrile rubber.

7. An intracavity magnetic resonance radio frequency coil as claimed in claim 5 wherein: the outer coaxial cable (9) is a flexible coaxial cable, and the inner coaxial cable (5) is a semi-rigid coaxial cable.

8. A method of using an intracavity magnetic resonance radio frequency coil as claimed in any one of claims 1 to 7 including the steps of:

(1) the air bag (1) is loaded into a target cavity in an uninflated state, and is guided by imaging of a body coil of an MRI system in the loading process to determine the position and position of the coil in the cavity;

(2) after the intracavity coil is loaded to the target area position, connecting the intracavity coil with a magnetic resonance spectrometer system;

(3) and inflating the air bag (1) to enable the upper surface coil (3) and the lower surface coil (4) to be attached to the target region tissue, adjusting the distance between the excitation coil (2) and the upper surface coil (3) and the lower surface coil (4) through inflation of the air bag (1), and finally performing magnetic resonance examination imaging.

Technical Field

The invention relates to the technical field of Magnetic Resonance Imaging (MRI), in particular to an intracavity magnetic resonance radio frequency coil and a using method thereof.

Background

The magnetic resonance imaging technology is widely applied to the field of medical imaging by the advantages of non-invasive detection, multi-nuclide, multi-parameter, high soft tissue resolution, imaging in any layer direction and the like, and is more and more popular with doctors and patients due to the characteristic that the magnetic resonance technology has no ionizing radiation particularly in the aspect of tumor tissue diagnosis.

In clinical examination and preclinical application research, in order to improve the signal-to-noise ratio of Nuclear Magnetic Resonance (NMR) signals and improve MRI image contrast, a body coil of a birdcage structure is generally used to excite spin nuclei in a target region, and a surface coil is used as a detection coil to receive signals. However, for organs and tissues in the deep layer of the human body, such as pathological changes in the stomach, tumors in the rectum, pathological changes in the uterus, etc., even if the conventional surface coil is tightly attached to the body surface, the filling factor of the conventional surface coil relative to the pathological changes is also sharply reduced, so that the signal-to-noise ratio of the acquired MRI image is sharply reduced, and a large error is brought to the diagnosis and analysis of clinical lesions, and even misdiagnosis is caused.

In addition, in magnetic resonance imaging, for example, CN106725477A discloses a vertical field magnetic resonance body intervention dedicated radio frequency coil and CN107811638A discloses a magnetic resonance system, wherein surface coils are arranged on the outer surface of the balloon, the surface coils are attached to the body surface through the balloon for magnetic resonance imaging, and when the surface coils arranged on the body surface are used for acquiring images of deep tissues or organs in the body, the surface coils are far away from the target area and are easily affected by other tissue signals between the target area and the surface coils, or even submerged; especially in the early stage of disease development, the collected images are difficult to be imaged, and further missed diagnosis and misdiagnosis are caused. In addition, the body coil is adopted for excitation, the body coil wraps the whole body, the volume of the inner space is large, the required radio frequency power is high, the radio frequency energy (SAR) absorbed by a patient is high when the radio frequency energy irradiates the whole body in the coil, the risk of potential burn to the patient is caused, and especially, the energy waste is caused relative to small focuses in the cavity.

In order to improve the defects of the conventional surface coil in the detection of the deep tissues or organs in the body and improve the contrast of the MRI image of the deep tissues in the body, it is necessary to improve the detection sensitivity of the tissues in the body or to adopt a new detection coil and method. While the conventional in vivo mri intracavity rf coil such as CN2699832Y discloses an mri intracavity rf coil that is opened by sliding a slide cylinder to form a desired shape, CN106199470A discloses a built-in mri rf receiving coil that is opened by a slide block to support an umbrella-shaped stent, and a flexible coil that is laid on a side support rod is opened during the unfolding process. The built-in radio frequency coil is easy to break a circuit of a circuit board in the unfolding process of the flexible coil; after being placed in the body, when the cavity is in a collapsed state, whether the slider or the sliding barrel moves relative to the human tissue, the patient may be injured and the comfort level of the patient may be reduced, and the slider is not convenient to move because the slider is placed in the body. Meanwhile, the structure is not easy to control the attachment of the main functional units of the coil to the focus of the inner wall of the cavity, in particular to an umbrella-shaped structure after being unfolded.

Disclosure of Invention

The invention provides an intracavity magnetic resonance radio frequency coil and a using method thereof, which are convenient to load in a patient body, reduce the uncomfortable feeling of the patient, improve the detection sensitivity to the maximum extent, prevent the circuit board circuit in a surface coil component from being broken, and effectively reduce the SAR value.

The technical scheme of the invention is realized as follows: an intracavity magnetic resonance radio frequency coil comprises an air bag loaded into a target cavity, wherein an intracavity coil is arranged in the air bag, the intracavity coil comprises a surface coil assembly and an excitation coil, the surface coil assembly is arranged on the inner surface of the air bag and used for exciting and collecting magnetic resonance signals of tissues of a target area, and the excitation coil is arranged in the air bag and matched with the surface coil and used for providing excitation coupling or receiving the magnetic resonance signals from the tissues of the target area.

Furthermore, the surface coil assembly comprises an upper surface coil arranged on the inner upper surface of the air bag and a lower surface coil arranged on the inner lower surface of the air bag, the exciting coil is arranged in the air bag between the upper surface coil and the lower surface coil, and the distance between the exciting coil and the upper surface coil and the distance between the exciting coil and the lower surface coil are adjusted by adjusting the inflating quantity of the air bag. Meanwhile, the close fit between the upper surface coil and the lower surface coil and the tissue of the target area can be ensured by adjusting the inflation quantity.

Furthermore, the upper surface and the lower surface of the air bag are both made of non-telescopic materials and have flexibility, the side wall of the air bag between the upper surface and the lower surface is made of elastic telescopic materials, and the surface coil assembly is an annular coil made of a flexible circuit board. The surface coil component is attached to the inner surface of the air bag and can be correspondingly changed along with the shape of the air bag. The material of the upper and lower surfaces of the air bag can prevent the circuit board circuit in the coil on the upper and lower surfaces from being broken.

Furthermore, the exciting coil comprises a coupling ring, one end of the coupling ring is arranged in the air bag, the other end of the coupling ring is connected with an internal coaxial cable arranged in the air bag, the internal coaxial cable is connected with the radio frequency connector on the surface of the air bag, and the internal coaxial cable is connected with the air bag through a sealing ring. The exciting coil is formed by a coupling ring structure, and energy is transferred to the surface coil in an electromagnetic induction mode, so that radio frequency feed of the surface coil is realized.

Further, the device also comprises an inner and outer connecting assembly, wherein the inner and outer connecting assembly comprises an air pipe connected with the air bag, an external coaxial cable connected with the radio frequency connector and a flexible sleeve wrapped on the outer sides of the air bag and the external coaxial cable, and the external coaxial cable is connected with the magnetic resonance spectrometer system.

Furthermore, the non-stretching material is polytetrafluoroethylene plastic, and the elastic stretching material is butadiene-acrylonitrile rubber.

Further, the outer coaxial cable is a flexible coaxial cable, and the inner coaxial cable is a semi-rigid coaxial cable.

A method of using an intracavity magnetic resonance radio frequency coil comprising the steps of:

(1) the air bag is loaded into a target cavity in an uninflated state, and the orientation and the position of the coil in the cavity are determined under the guidance of the imaging result of the body coil of the MRI system in the loading process;

(2) after the intracavity coil is loaded to the target area position, connecting the intracavity coil with a magnetic resonance spectrometer system;

(3) and inflating the air bag to enable the upper surface coil and the lower surface coil to be attached to the target region tissue, adjusting the distance between the exciting coil and the upper surface coil and the distance between the exciting coil and the lower surface coil through inflating the air bag, and finally performing magnetic resonance examination imaging.

The invention has the beneficial effects that:

the air bag structure of the radio frequency coil in the cavity is convenient to load into the body of a patient, so that the discomfort of the patient is reduced; the upper surface coil and the lower surface coil which are manufactured by the flexible circuit board are used as radio frequency coils, so that the radio frequency coils can be attached to target area tissues, the filling factor of the radio frequency coils is improved, and the detection sensitivity is improved to the greatest extent; the built-in surface coil assembly is tightly attached to the tissue to be detected, so that artifacts generated by other tissues or organs can be reduced, a detection result with higher quality can be provided for clinical diagnosis, the air bag part loaded into the body of a patient is connected with an external device, such as an external tuning matching circuit and a magnetic resonance spectrometer system, through the internal and external connecting assembly, the separation of the internal part and the external part of the device is realized, and the comfort level of the patient is improved to the maximum extent; the intracavity radio frequency coil of the invention needs small radio frequency power when being used as a receiving and transmitting integrated coil, thereby effectively reducing SAR value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of an intracavity magnetic resonance RF coil of the present invention;

FIG. 2 is a schematic view of the structure of the bladder;

FIG. 3 is a schematic diagram of an external tuning matching circuit;

figure 4 is a schematic diagram of an intracavity magnetic resonance radio frequency coil of the present invention.

The air bag type coaxial coupling comprises an air bag 1, an exciting coil 2, an upper surface coil 3, a lower surface coil 4, an inner coaxial cable 5, a radio frequency connector 6, a sealing ring 7, an air pipe 8, an outer coaxial cable 9, a flexible sleeve 10, an external tuning matching circuit 11, a matching capacitor 12, a tuning capacitor 13, a quick air pipe connector 14, an input end 15 and an output end 16 of a series-parallel circuit network.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.

Example one

As shown in fig. 1-3, an intracavity magnetic resonance radio frequency coil includes an airbag 1 for loading into a target cavity, an intracavity coil is disposed in the airbag 1, the intracavity coil includes a surface coil component and an excitation coil 2, the surface coil component is disposed on an inner surface of the airbag 1, the surface coil component includes an upper surface coil 3 attached to an inner upper surface of the airbag 1 and a lower surface coil 4 attached to an inner lower surface of the airbag 1, the upper surface coil 3 and the lower surface coil 4 are both annular coils made of a flexible circuit board, and are used for exciting and collecting a magnetic resonance signal of a target region tissue. The upper surface coil 3 and the lower surface coil 4 are attached to the inner surface of the air bag 1, can be correspondingly changed along with the shape of the air bag 1, and ensure that the upper surface coil 4 and the lower surface coil 4 are tightly attached to the target area tissue by controlling the inflation quantity.

Meanwhile, in order to prevent the circuit board lines in the upper surface coil 3 and the lower surface coil 4 from being broken, the upper surface and the lower surface of the air bag 1 are both made of non-telescopic materials and have high flexibility, such as polytetrafluoroethylene plastics and the like, the air bag 1 is shaped like a common hot water bag structure, the flexible circuit boards are attached to the upper surface and the lower surface in the air bag 1, and four side surfaces of the air bag 1 are made of elastic telescopic materials, such as butadiene-acrylonitrile rubber.

The exciting coil 2 comprises a coupling ring, one end of the coupling ring is arranged in the air bag 1 and is arranged between the upper surface coil 3 and the lower surface coil 4, the other end of the coupling ring is connected with an internal coaxial cable 5 arranged in the air bag 1, the internal coaxial cable 5 is a semi-steel coaxial cable, the internal coaxial cable 5 is connected with a rapid radio frequency connector 6 on the surface of the air bag 1, and the internal coaxial cable 5 is fixedly and hermetically connected with the air bag 1 through a sealing ring 7. The exciting coil 2 is formed by a coupling ring structure, and energy is transferred to the upper surface coil 3 and the lower surface coil 4 in an electromagnetic induction mode to realize radio frequency feed of the upper surface coil 4 and the lower surface coil 4; the upper surface coil 3 and the lower surface coil 4 receive the magnetic resonance signals of the tissues of the target area, and transmit the signals to the exciting coil 2 in an electromagnetic induction mode so as to transmit the signals to a receiving link of the spectrometer.

The utility model provides an intracavity magnetic resonance radio frequency coil, still includes inside and outside coupling assembling, inside and outside coupling assembling includes the trachea 8 that links to each other with gasbag 1, and the one end that gasbag 1 was kept away from to trachea 8 is connected with quick air pipe joint 14, the outside coaxial cable 9 that links to each other with radio frequency joint 6 to and the flexible sleeve 10 of suit in gasbag 1 and outside coaxial cable 9 outside, outside coaxial cable 9 links to each other with magnetic resonance spectrometer system. The outer coaxial cable 9 is a flexible coaxial cable.

An intracavity magnetic resonance radio frequency coil also comprises an external tuning matching circuit 11, wherein the external tuning matching circuit 11 comprises a series-parallel circuit network consisting of a matching capacitor 12, a tuning capacitor 13 and a resistance element, the output end 16 of the series-parallel circuit network is connected with an external coaxial cable 9, and the input end 15 is connected with a radio frequency coil feed connector of a magnetic resonance spectrometer system.

Example two

The use method of the intracavity magnetic resonance radio frequency coil in the first embodiment comprises the following steps:

(1) the air bag 1 is loaded into a target cavity in a tested body in an uninflated state, namely a collapsed state, so that discomfort of a patient is reduced, and the position of an intracavity coil are determined under the guidance of a body coil imaging result of an MRI system in the loading process of the intracavity coil;

(2) after the intracavity coil is loaded to the target area position, as shown in fig. 4, the intracavity coil is connected with the magnetic resonance spectrometer system, i.e. the fast radio frequency connector 6 is connected with the external coaxial cable 9 and is connected with the internal coaxial cable 5, the other end of the external coaxial cable 9 is connected with the output end 16 of the series-parallel circuit network, and the input end 15 of the series-parallel circuit network is connected with the radio frequency coil feed connector at the radio frequency transceiving switch of the magnetic resonance spectrometer system;

(3) and inflating the air bag 1 to enable the upper surface coil 3 and the lower surface coil 4 to be attached to the target region tissue, adjusting the distance between the exciting coil 2 and the upper surface coil 3 and the lower surface coil 4 by inflating the air bag 1, tuning and matching by an external tuning matching circuit 11, and finally performing magnetic resonance examination imaging after tuning is finished.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.