JP5657867B2 - High frequency coil unit - Google Patents

Description

  The present invention relates to a high-frequency coil unit that is suitable for use in a magnetic resonance imaging (MRI) apparatus that images the inside of a subject using a magnetic resonance phenomenon, and that is used while attached to the subject.

  The magnetic resonance phenomenon resonates with a high-frequency (RF) magnetic field that rotates at a specific frequency (resonance frequency) according to its intrinsic magnetic moment and existing magnetic field strength when a group of target nuclear spins is placed in the magnetic field. In this relaxation process, a signal (magnetic resonance signal) is generated. A magnetic resonance imaging apparatus is an apparatus that acquires chemical and physical microscopic information of a substance by using this magnetic resonance phenomenon and images it. The RF magnetic field is applied as an RF pulse, also called RF signal transmission. The magnetic resonance signal is received as an RF signal. An RF coil is used for transmission and reception of the RF signal.

  There are RF coils for transmission, reception, and transmission / reception. As for the RF coil for exclusive use for reception and transmission / reception, those having various shapes are prepared according to the part to be imaged. Many of such local RF coils have a structure that is attached to a subject so as to cover the periphery of the region to be imaged so as to arrange the electric wire so as to surround the region of the region to be imaged. For this reason, in a state where this type of RF coil is attached to the subject, it is difficult for an engineer or the like to visually observe the state of the part to be imaged.

  In particular, the RF coil for photographing the head is mounted so as to cover the subject's head, so that it is difficult for an engineer or the like to confirm the facial expression of the subject, and the subject has a feeling of pressure. I will give it.

  Therefore, various devices have been made for the purpose of reducing the subject's feeling of pressure. For example, in Patent Document 1, in a coil provided to wind a subject, the conductive portion is made of a light-transmitting and conductive material such as a water-soluble conductive polymer or a transparent conductive film, and a coil circuit. It is disclosed that the cover that covers the cover is made of a material such as light-transmitting plastic or vinyl that has light-transmitting properties. Patent Document 2 discloses an RF coil in which a bar-shaped conductor such as a copper bar is covered with a transparent coating.

JP 2003-10146 A JP 2001-149339 A

  According to the technique of Patent Document 1, since the conductivity of the water-soluble conductive polymer or the transparent conductive film is relatively low, it has been difficult to ensure sufficient RF signal transmission / reception efficiency. In addition, long-term use and changes in physical property values of the polymer material due to heat are problematic.

  According to the technique of Patent Document 2, since the rod-shaped conductor is visible to the subject, there is a fear that the subject may feel uneasy.

  In addition, in a high-function RF coil, not only a conductor but also an electric circuit connected thereto is mounted. Circuit elements such as capacitors and diodes included in such an electric circuit can be seen by the subject in both of the techniques of Patent Document 1 and Patent Document 2, and may cause anxiety to the subject. there were.

  The present invention has been made in consideration of such circumstances, and the purpose of the present invention is to reduce the feeling of pressure and anxiety given to the subject while the appearance of the imaging region from the outside even in the wearing state. An object of the present invention is to provide an RF coil unit that can be confirmed.

A high-frequency coil unit according to a first aspect of the present invention includes a high-frequency coil including an electric wire and an electric circuit connected to the electric wire, an opaque material, covers the electric wire and the electric circuit, and includes a head of a subject. A coil cover having a space for disposing a portion as a subject, and a transparent material, and the subject having the head disposed inside the coil cover to confirm the state of the subject. A transparent attached to at least a region covering the upper part of the face part from the vicinity of the head of the subject in the coil cover so that at least a part of the face part of the examiner is visible from the outside of the coil cover. A member.

A high-frequency coil unit according to a second aspect of the present invention includes a high-frequency coil including an electric wire and an electric circuit connected to the electric wire, and a transparent material, for covering the high-frequency coil and arranging a human head. A coil cover having a space inside and an opaque material, and at least a part of the face portion of the head is visible from the outside of the coil cover, while the head is inside the coil cover. A masking member attached to the coil cover so as to make the high-frequency coil invisible from a human body arranged.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to confirm the mode of the imaging | photography site | part from the outside also in a mounting state, reducing the feeling of pressure and anxiety given to a subject.

The top view which shows the external appearance of the RF coil unit 1 which concerns on the 1st Embodiment of this invention. The top view which shows the external appearance of the RF coil unit 1 which concerns on the 1st Embodiment of this invention. The top view which shows the external appearance of the RF coil unit 1 which concerns on the 2nd Embodiment of this invention. The top view which shows the external appearance of the RF coil unit 1 which concerns on the 2nd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
1 and 2 are plan views showing the appearance of the RF coil unit 1 according to the first embodiment. FIG. 2 shows a state seen from the right side of FIG.

  The RF coil unit 1 is used for photographing the head, and is used by being mounted on the head 100 of the subject as shown in FIG. The RF coil unit 1 is divided into an upper unit 11 and a lower unit 12 for easy attachment to and removal from the head 100. That is, with only the lower unit 12 placed on the bed top of the magnetic resonance imaging apparatus (MRI apparatus), the subject is placed on the bed top so that the head 100 rides on the lower unit 12. After laying down, the upper unit 11 is put on the head 100 and coupled to the lower unit 12.

  The upper unit 11 and the lower unit 12 include basic structures 11a and 12a, respectively. The basic structures 11a and 12a are made of a material such as polycarbonate resin having rigidity capable of stably maintaining the shape, and are molded so as to form a space for accommodating the head 100 therein. The basic structures 11a and 12a are opaque.

  The upper unit 11 includes a copper pattern 11b, a circuit board 11c, and a transparent member 11d in addition to the basic structure 11a. The copper pattern 11b is a pattern formed by copper foil or a conductive wire inside the basic structure 11a. The copper pattern 11b receives a magnetic resonance signal by inducing an electromotive force by a magnetic resonance phenomenon generated in the head 100. Alternatively, the copper pattern 11 b receives an RF signal and generates an RF magnetic field to be applied to the head 100. The circuit board 11c is disposed inside the basic structure 11a and is electrically connected to 12a. An electric circuit is mounted on the circuit board 11c. This electric circuit tunes the resonance frequency of the coil made of the copper pattern 11b to the frequency of the magnetic resonance signal. Thus, the basic structure 11a functions as a coil cover that covers the copper pattern 11b and the circuit board 11c. The transparent member 11d is disposed so as to cover the opening formed in the basic structure 11a. For the transparent member 11d, for example, a transparent material such as acrylic is used. The position where the transparent member 11d is disposed avoids the positions where the copper pattern 11b and the circuit board 11c are disposed, and the face of the head 100 disposed inside the RF coil unit 1 can be viewed from the outside of the RF coil unit 1. It is prescribed as follows. The position where the transparent member 11d is arranged is more preferably the head placed through the opening of the imaging space by a camera installed outside the imaging space in a state of being placed in the imaging space of the MRI apparatus. It is determined so that the face of unit 100 can be photographed. Further, it is desirable that the transparent member 11d has a smooth shape so that the optical image of the face of the head 100 can be transmitted without being significantly distorted.

  Thus, according to the RF coil unit 1, the transparent member 11 d functions as a window for making the face of the head 100 arranged inside the RF coil unit 1 visible from the outside of the RF coil unit 1. An engineer or the like can visually observe the face of the head 100 through this window, and the state of the subject can be easily confirmed. In addition, since the subject can view the outside of the RF coil unit 1 through the window, the feeling of pressure on the subject can be reduced. Since the copper pattern 11b and the circuit board 11c are covered with the opaque basic structure 11a, the copper pattern 11b and the circuit board 11c are not visible from either the inside or outside of the RF coil unit 1, so that the subject does not feel uneasy. And since the copper pattern 11b does not need to be transparent, it can use materials with high conductivity, such as copper foil and a copper wire, and can fully ensure transmission / reception efficiency.

(Second Embodiment)
3 and 4 are plan views showing the appearance of the RF coil unit 2 according to the second embodiment. FIG. 4 shows a state seen from the right side of FIG.

  The RF coil unit 2 is used for photographing the head, and is used by being mounted on the subject's head 100 as shown in FIG. The RF coil unit 2 is divided into an upper unit 21 and a lower unit 22 for easy attachment to and removal from the head 100. That is, with only the lower unit 22 placed on the bed top plate of the MRI apparatus, the subject is laid on the bed top plate so that the head 100 rides on the lower unit 22, and then the upper unit 21 is put on the head 100 and coupled to the lower unit 22.

  The upper unit 21 and the lower unit 22 include basic structures 21a and 22a, respectively. The basic structures 21a and 22a are made of a material having rigidity capable of stably maintaining the shape, and are molded so as to form a space for accommodating the head 100 therein. The basic structure 21a is made of a transparent material such as acrylic. Further, it is desirable that the basic structure 21a has a smooth shape so that the optical image of the face of the head 100 can be transmitted without being significantly distorted. The basic structure 22a is made of a material such as polycarbonate resin or acrylic. The material may be opaque or transparent.

  The upper unit 21 includes a copper pattern 21b, a circuit board 21c, and a masking member 21d in addition to the basic structure 21a. The copper pattern 21b is a pattern formed by copper foil or a conductive wire inside the basic structure 21a. The copper pattern 21 b receives a magnetic resonance signal by inducing an electromotive force by a magnetic resonance phenomenon generated in the head 100. Alternatively, the copper pattern 21 b receives an RF signal and generates an RF magnetic field to be applied to the head 100. The circuit board 21c is disposed inside the basic structure 21a and is electrically connected to 22a. An electric circuit is mounted on the circuit board 21c. This electric circuit tunes the resonance frequency of the coil made of the copper pattern 21b to the frequency of the magnetic resonance signal. Thus, the basic structure 21a functions as a coil cover that covers the copper pattern 21b and the circuit board 21c. The masking member 21d is provided on the outer surface and the inner surface of the basic structure 21a so as to mask the copper pattern 21b and the circuit board 21c, respectively. An opaque material is used for the masking member 21d. The masking member 21d may be a sheet-like member or a paint-like member. It is desirable that the masking member 21d has a minimum size that can mask the copper pattern 21b and the circuit board 21c. At least the face of the head 100 arranged inside the RF coil unit 2 is provided so that it can be seen from the outside of the RF coil unit 2. More preferably, the masking member 21d is placed in the imaging space of the MRI apparatus, and the face of the head 100 is moved through the opening of the imaging space by a camera installed outside the imaging space. Provided so as not to interfere with shooting.

  Thus, according to the RF coil unit 2, since the basic structure 21 a is transparent, an engineer or the like can visually observe the face of the head 100 disposed inside the RF coil unit 2 from the outside of the RF coil unit 2. Thus, the state of the subject can be easily confirmed. In addition, since the subject can visually observe the outside of the RF coil unit 2, the feeling of pressure on the subject can be reduced. And since the copper pattern 21b and the circuit board 21c are masked by the masking member 21d and cannot be seen from both inside and outside of the RF coil unit 2, there is no sense of anxiety to the subject. And since the copper pattern 21b does not need to be transparent, materials with high electrical conductivity, such as copper foil and a copper wire, can be used, and transmission / reception efficiency can fully be ensured.

  This embodiment can be variously modified as follows.

  Even if the copper patterns 11b and 21b and the circuit boards 11c and 21c are visible from the outside of the RF coil unit 1, the copper pattern 11b and 21b and the circuit boards 11c and 21c are visually observed from the subject to whom the copper patterns 11b and 21b are attached. Since this is not possible, the effect of reducing anxiety of the subject can be obtained.

  A member that refracts light such as a refracting sheet or a prism sheet is used for the basic structures 11a and 21a or the transparent member 11d, and a light image refracted by these members can be viewed from the outside of the RF coil unit 1. You may comprise so that it may do.

  The present invention can also be applied to an RF coil unit for imaging other parts than the head.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  This embodiment can be variously modified as follows.

  DESCRIPTION OF SYMBOLS 1,2 ... RF coil unit, 11, 21 ... Upper unit, 12, 22 ... Lower unit, 11a, 12a, 21a, 22a ... Basic structure, 11b, 21b ... Copper pattern, 11c, 21c ... Circuit board, 11d ... transparent member, 21d ... masking member.

Claims (4)

A high-frequency coil including an electric wire and an electric circuit connected to the electric wire;
A coil cover made of an opaque material, covering the electric wire and the electric circuit, and having a space for arranging the subject's head as a subject,
It is made of a transparent material, and at least a part of the face part of the subject can be visually observed from the outside of the coil cover in order to confirm the state of the subject with the head arranged inside the coil cover. As described above , a high-frequency coil unit comprising: a transparent member attached to at least a region covering the upper part of the face from the vicinity of the top of the subject of the coil cover . The high-frequency coil unit is arranged and used in a cavity formed in a gantry of a magnetic resonance apparatus,
The said transparent member is attached to the said coil cover so that at least one part of the said face part can be visually recognized from the outer side of the said cavity in the state which has arrange | positioned the said high frequency coil unit in the said cavity. Item 4. The high frequency coil unit according to Item 1. A high-frequency coil including an electric wire and an electric circuit connected to the electric wire;
A coil cover made of a transparent material, covering the high-frequency coil and having a space for placing the head of the human body inside,
It is made of an opaque material, and at least a part of the face portion of the head is visible from the outside of the coil cover, and the high-frequency coil is visually observed from a human body in which the head is disposed inside the coil cover. A high-frequency coil unit comprising a masking member attached to the coil cover so as to be impossible.   The high frequency coil unit according to claim 3, wherein the masking member is attached to the coil cover so that the high frequency coil is not visible from the outside of the coil cover.

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