KR101635641B1 - Microstrip-based RF surface receive coil for the acquisition of MR images and RF resonator having thereof - Google Patents

Abstract

The present invention relates to a structure of a microstrip-based surface coil, and more particularly, to a microstrip-based RF surface-receiving coil having a surface-receiving coil in a double-turn configuration for use in a small volume coil at 1T To an RF resonator.
A microstrip-based RF surface-receiving coil according to the present invention is formed in a rectangular shape so that an outer coil portion and an inner coil portion are connected to each other in succession. The outer coil portion has a T- And a round portion is formed at an inner edge of the inner coil portion.
The RF resonator according to the present invention comprises a microstrip-based RF surface-receiving coil, a coaxial cable connected to the end of the receive coil, a tolloid connected to the coaxial cable and compensating for inductance of the coaxial cable, Lt; / RTI > and a tuning capacitor connected to the output terminal.

Description

TECHNICAL FIELD The present invention relates to a microstrip-based RF surface receiving coil for acquiring a magnetic resonance medical image, and an RF resonator having the RF surface receiving coil.

The present invention relates to a structure of a microstrip-based surface coil, and more particularly, to a microstrip-based RF surface-receiving coil having a surface-receiving coil in a double-turn configuration for use in a small volume coil at 1T To an RF resonator.

Generally, magnetic resonance imaging (MRI) is based on the principle of nuclear magnetic resonance (MRI). It is a diagnostic device that images the spatial distribution of hydrogen nuclei present in the human body and displays the state of the human body.

Magnetic Resonance Imaging (MRI) is divided into a magnetizing unit for forming a primary magnetic field and a magnetizing unit for forming a secondary magnetic field in order to induce a resonance phenomenon. The magnetizing unit for forming a secondary magnetic field includes a seaming coil, , And a high-frequency coil. In particular, the high-frequency coil receives the RF signal that emits as it loosens after the float is excited. At this time, the state of the human body is imaged based on the received RF signal.

In the design of a standardized RF coil, there is loss of transmission power and received signal due to radiation force and current flow from the coil surface. In order to reduce the skin effect and radiation loss of a coil based on a microstrip, it is used in a high frequency or microwave antenna or a microwave integrated circuit. Particularly, the use of a microstrip-based coil is advantageous in terms of miniaturization, simplicity, So that it can be applied to microwave circuit manufacturing technology.

In previous studies, microstrip RF surface receive coils were tested at 300 MHz (proton laminar frequency at 7 T). The results of this experiment demonstrate that the concept of microstrip transmission is applicable to improve existing surface-receiving coils without RF shielding in the super-magnetic field. RF surface coils based on the concept of microstrip transmission lines have also been shown to be appropriate and efficient in ultra-high field MRI scanners.

Also, in the design of the RF surface coil, the tuning capacitance and the matching capacitance are installed in the vicinity of the receive coil loop. These capacitances should be non-magnetic and their magnitude should be considered according to the magnitude of the magnet bore or magnetic field. In the case of limited space, the capacitance is placed outside the magnet using the extension shaft, and the RF resonator is fixed to match the tuning capacitance located outside the magnet.

The magnitude of the magnetic field and the size of the magnet bore in the MRI scanner should be considered in selecting the physical length of the RF resonator and the size of the loop itself of the receive coil. In such a case, the RF resonator corresponds to a case where the RF coil is constituted by a component other than the receive coil, for example, a transmission line.

The length of the RF resonator is nλ / 2 (n = integer, λ is the main cavity wavelength of the MRI scanner) and is inversely proportional to the intensity of the magnetic field. Although the number of MRI studies at high- and ultra-high magnetic field strengths (> 3 T) is increasing, MRI studies at relatively low magnetic field intensities (less than 1.5 T) are still in a standstill.

Previous studies applying the concept of a microstrip transmission line that applies to the strength of a low magnetic field with a permanent magnet and a small magnet bore are not known. In order to fabricate a microstrip-based RF coil for use in low magnetic fields and / or small magnet bores, a method of designing an RF resonator having a long physical length that can be applied in a small bore is required.

Japanese Patent Application Laid-Open No. 10-2013-0029931, index RF coil unit for magnetic resonance imaging Patent Publication No. 10-0351072, High Frequency Coil for Magnetic Resonance Imaging Apparatus Japanese Patent Application Laid-Open No. 10-1260074, an RF shielding method, an MRI apparatus, and a transmitting and receiving surface coil

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an RF surface receiver coil having a permanent magnet and a small volume transmission coil at 43.9 MHz (proton frequency at 1 T) and a small microstrip transmission line is designed. There is a purpose.

In addition, the problems to be solved by the present invention are not limited to the above-mentioned problems. It is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention.

A microstrip-based RF surface-receiving coil according to the present invention is formed in a rectangular shape so that an outer coil portion and an inner coil portion are connected to each other in succession. The outer coil portion has a T- And a round portion is formed at an inner edge of the inner coil portion.

The receiving coil may have a rectangular shape and may have a rectangular shape. The receiving coil may be double-curved inwardly from one end and connected to the other end.

Further, the T-shaped cutout is formed in an area within 1/2 of the outer side of the coil width.

The resonance wavelength of the receive coil is determined by the following equation.

는 유효 유전상수이고,

는 기재의 유전율이고, W는 구리박판의 폭이고, H는 기재의 두께이다.However, λ ₀ is the wavelength of light in free space,

Is an effective dielectric constant,

W is the width of the copper foil, and H is the thickness of the substrate.

The RF resonator according to the present invention comprises a microstrip-based RF surface-receiving coil, a coaxial cable connected to the end of the receive coil, a tolloid connected to the coaxial cable and compensating for inductance of the coaxial cable, And the tuning capacitance.

According to the microstrip-based RF surface-receiving coil according to the present invention, the RF surface-receiving coil is designed on the basis of the microstrip, so that it can be easily and simply implemented without RF shielding.

In addition, microstrip-based double-turn coils exhibit excellent characteristics as surface-receiving coils used in small-diameter, low-magnetic fields, which are simple, efficient, and useful in application and implementation in design.

Further, when the RF surface-receiving coil according to the present invention is formed of a double-turn coil, the outer coil loop of the double-turn coil is compensated by the uniform current density of the single-turn coil, Can be solved.

1 illustrates a microstrip-based RF surface receive coil according to an embodiment of the present invention.
Fig. 2 shows measurement of the reflection coefficient of the RF resonator.
FIG. 3 illustrates an RF resonator having a microstrip-based RF surface-receiving coil according to the present invention.
4 shows a comparison of the distribution of B1 transmission and signal intensity measured by simulation in a phantom spaced vertically from a microstrip-based surface coil.
FIG. 5 shows the FID (Free Induction Decay) of a phantom using a single-turn shape and a double-turn-shaped receive coil.
6 shows an MR image of a gel phantom obtained from a surface-receiving coil of a single-turn shape and a double-turn shape.
FIG. 7 shows a normalized SNR shape of a gel phantom appearing in a center axis slice from left to right using a single-turn and double-turn microstrip coil and a volume-receiving coil.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the specification, a single-turn coil refers to a coil formed by bending a coil thin plate having a long length into a substantially rectangular shape, and a two-turn coil refers to a coil having a long length And the coil thin plate is formed by forming an outer coil loop and an inner coil loop in such a manner that the coil thin plate is continuously bent in a rectangular shape from the outside to the inside.

Further, the RF surface receiving coil, the RF receiving coil, the surface receiving coil, and the receiving coil all refer to the same components.

First, a microstrip-based surface coil according to the present invention is preceded by a phantom preparation process.

Phantom is a substance that has a volume very close to the biological density and effective atomic number. An organic hydrophilic polymer, TX151 gel (Oil Center Research Intl.L.L.C., Lafayette, LA), was used as the material of the phantom. 20 g of TX151 powder was mixed with 200 g of deionized water at 6 占 폚. The solution was then slowly mixed in a beaker with 1,000 ml. The mixture of water and powder was soaked until the powder was uniformly dispersed.

Once the mixture is homogeneously mixed and homogeneous in the beaker, the bubbles in the solution are generated and the beaker is vacuumed to remove it. The mixture is then placed in a 50 ml beaker and heated in a 70 ° C water bath for 1 hour until the mixture hardens.

After the beaker is covered with a plastic cover, the mixture is kept in a gel state at room temperature for 24 hours. The phantom is cut to fit the phantom folder (2.5 x 2.5 x 1.0 cm ³ ) for NMR (Nuclear Magnetic Resonance) signal acquisition device and MR (magnetic resonance) image acquisition device.

Inversion Recovery (IR) and Carr Purcell Meiboom Gill (CPMG) pulse sequences were used to measure the vertical (T1) and horizontal (T2) relaxation times of the gel phantom. Ten measurements were made and the standard deviation (s.d.) was calculated. As a result, T1 and T2 of the TX151 gel phantom were 1134.16 (± 86.5) and 68.2 (± 5.1) ms, respectively.

Thus, the RF resonator is constructed using the prepared phantom. The RF resonator comprises a microstrip-based RF surface receive coil. 1 illustrates a microstrip-based RF surface receive coil according to an embodiment of the present invention. In order to demonstrate the convenience and effect of the explanation, a single-turn coil and a double-turn coil will be described for comparison.

The microstrip-based RF surface-receiving coil according to the present invention is designed to be applied to a 1T Aspect MR imaging system (Aspect Magnet Technologies, Israel), a 4-channel receiver, and a 6 cm diameter x 10 cm solenoid volume transceiver coil. Here, the Aspect MRI system is connected to a Tecmag console (Technology for magnetic resonance, Houston, TX).

FIG. 1 (a) shows a microstrip-based RF surface-receiving coil formed by a single-turn coil according to an embodiment of the present invention. FIG. 1 (b) RF surface receive coil.

The microstrip-based RF surface-receiving coil formed by the double-turn coil according to the present invention has a rectangular shape so that the outer coil part 100 and the inner coil part 200 are connected successively, And a round portion 210 is formed at an inner edge of the inner coil portion.

The T-shaped incision part forms a first incision groove 111 and a second incision groove 112 formed in the longitudinal direction of the outer coil part in the first incision groove in the outer coil part. The incision groove is formed in the width direction of the outer coil section and the second incision groove is formed in the direction perpendicular to the direction in which the first incision groove is formed, that is, the longitudinal direction of the outer coil section.

The first and second cutouts form a first protrusion 110a and a second protrusion 110b protruding from the first cutout groove on the outer side of the outer coil section.

More specifically, it is formed so as to continuously extend from one end to the other end so as to have a square shape. Referring to the drawing, a T-shaped incision 110 formed on the outer side of the surface-receiving coil is formed in an area within a half of the width of the coil part. Referring to the drawing, a region a in which the T-shaped cutout portion 110 is formed is formed in an area within 1/2 of the outer side of the coil width b.

On the other hand, a gap is formed between the outer coil portion and the inner coil portion of the double-turn coil. In the case of a rectangular coil, the gap in the edge region affects the coil characteristics such as penetration depth. The coil characteristics can be improved by adjusting the gap distance of the edge region. Preferably, the shape of the inner coil part is formed in various shapes such as a round shape and a chamfer shape in the corner area, and a gap distance between the outer coil part and the inner coil part in the corner area is set to be a distance between the outer coil part and the inner coil part The gap is formed to be larger or smaller than the gap distance. That is, in the double-turn coil, the corner and sides of the rectangular shape have different gap sizes. Also, considering the distribution of signal strength, the gap size of the four corners can be adjusted so that they are not necessarily the same.

A typical microstrip transmission line consists of a copper sheet and a ground plate, where the copper sheet and the ground plate are spaced apart from each other by the dielectric material. To select dielectric materials, four different materials were tested. Three different materials (Teflon1 PTFE, glass-filled PTFE, plexiglass) including G10 (FR4) were prepared. Each material was formed with the same size and shape and tested. (Hewlett Packard Model 8725A, 300 KHz - 1.3 GHz).

 [Table 1] Q value of RF surface receiving coil using four different base materials

Table 1 shows a comparison of the Q values of RF receive coils having double-turn shapes with four different base materials. The selectivity Q values of the four different materials used to form the RF coils of the 1T MRI scanner were measured. G10 (FR4) showed a higher Q value than the rest of them.

The no-load Q of microstrip coils with G10 (FR4) was 148. The resonance frequencies of the single-turn coil and the double-turn coil were 43.867 and 43.908, respectively. The lowest frequency and the sweep frequency measured by varying capacitance were 34.4 MHz and 53.3 MHz, respectively.

Fig. 2 shows measurement of the reflection coefficient of the RF resonator. The reflection coefficient (S ₁₁ ) of the RF resonator was measured at 43.9 MHz. Referring to the figure, the reflection coefficient S ₁₁ is -40 dB. This section shows good impedance matching.

The microstrip-based RF surface-receiving coil according to the present invention has a micro-strip RF surface-receiving coil in the form of a single-turn coil and a double-turn coil having a square shape of 2.5 × 2.5 cm ² . Microstrip conductors and ground plates were fabricated using backside adhesive copper tape (3M, St. Paul, Minn.). The width W of the copper thin plate is 2 mm, and the height H thereof is 0.8 mm. The gap between the inner strip and the outer strip of the double-turn coil was 1 mm.

The resonant wavelength (?) Of the microstrip RF receive coil is calculated as follows.

는 유효 유전상수이다.
Where ₀ is the wavelength of light in free space,

Is an effective dielectric constant.

)과 유효 유전상수 사이의 관계는 다음과 같다.The dielectric constant of the substrate

) And effective dielectric constant is as follows.

W / H 1;

W / H >1;

Where W is the width of the copper foil and H is the thickness of the substrate.

According to the calculation, the RF resonator is matched to 50 at 43.9 MHz, and the resonant wavelength (454 cm) is calculated using equations [1] and [3]. The physical length of the RF resonator (nλ / 2, n = integer, λ is the dominant wavelength of the MRI scanner) is 227, 454, and 681 cm.

The minimum length (? / 2) of the microstrip-based RF surface receiving coil according to the present invention is 227 cm. To install a square-shaped loop of 2.5 x 2.5 cm ² inside a volume transfer coil with a diameter of 6 cm, a 217 cm long coaxial cable is required. Instead of long coaxial cables, a small length inductor (tolloid) with a ferrite core (0.68 cm ID, 0.18 cm OD, and a thickness of 0.31 cm) was wound 40 times with wire. The inductance of the tolldo is 2.3H. A small microstrip loop and a 40 cm long coaxial cable (RG-58 C / U) were placed inside a 10 cm long volume transfer coil. The RF coil circuit is connected to a preamplifier with a gain of 29dB.

FIG. 3 illustrates an RF resonator having a microstrip-based RF surface-receiving coil according to the present invention.

Referring to the drawings, there is shown a schematic view (a) of an RF resonator for explaining a microstrip-based surface receiving coil loop (b), in which an inductor having a predetermined length, a matching capacitor and a tuning capacitor are connected (c) Coaxial cable is used. The tolldo and the two capacitors (round part) (d) are located on the outside of the magnet.

A long coaxial cable is required to form a coil loop having a small square shape provided in a small magnet bore. Instead of long coaxial cables, an elongated inductor (talloid) is used to couple the small coil loop of the RF resonator with the matching and tuning capacitances. This is because the inductance of the microstrip RF receive coil can be substituted.

Applying tolloids is easier, simpler, and more efficient than increasing capacitance. Because of the mutual matching problem between the tolloid and the RF coil loops, the tolloids have been removed from the coil loops.

Hereinafter, the characteristics of the microstrip-based RF surface receiving coil constructed as described above will be described. The characteristics of the coil are as follows. The B ₁ transmission and the Q value thereof are examined. Next, the relationship between the W / H ratio and the no-load Q value is examined. In addition, the SNR of the obtained coil was calculated.

It is important to evaluate the characteristics of B ₁ transmission and Q value as a function of the vertical distance of the surface coil, since B ₁ transmission is a very important factor in determining the performance of the surface coil.

Then, we compare the B ₁ penetration depth obtained from the simulation and the comparative measurement, and examine the relationship between B ₁ transmission and W / H and the relationship between no-load Q factor and W / H. This is because the ratio of W / H is an important factor in the design of an optimized microstrip-based receiver coil. Next, the B ₁ penetration depth and the no-load Q value according to the W / H ratio are examined.

First, the B1 penetration depth and the no-load Q value according to the W / H ratio are as follows. Table 2 shows B ₁ transmission and no-load Q values according to the ratio of W / H.

=4.4)와 loss tangent(tanδ =0.02 at 2.4GHz)를 갖는 G10(FR4)가 사용되었다. 사각 형상을 갖는 코일 루프의 크기는 2.5×2.5cm²(W=2mm)이다. B₁ 투과와 무부하 Q 값은, 기재의 두께(H= 0.8, 1.0, 1.3, 2.0, 4.0, 8.0 그리고 1.0mm)를 변화시켜서 W/H 비율에 따른 함수로서 측정하였다.A microstrip-based RF surface-receiving coil formed in a double-turn configuration has a dielectric constant (

= 4.4) and a loss tangent (tan δ = 0.02 at 2.4 GHz). The size of the coil loops having a rectangular shape is 2.5 x 2.5 cm ² (W = 2 mm). The B ₁ transmission and no-load Q values were measured as a function of the W / H ratio by varying the thickness of the substrate (H = 0.8, 1.0, 1.3, 2.0, 4.0, 8.0 and 1.0 mm).

The B ₁ penetration depth was measured in a 4 cm diameter × 4 cm long semi-cylindrical phantom filled with a solution of 5 mM CuSO 4. As a result, the microstrip coil was compared with a 2.8 cm diameter circular surface coil with four split capacitors (= 64 pF).

[Table 2] Comparison of B ₁ transmission and no-load Q value according to W / H ratio

Referring to Table 2, when W / H ratios were 2.5, 1 and 0.2, the penetration depths of B ₁ were 1.9, 2.4 and 2.4, respectively, and no-load Q values were 148, 112 and 88, respectively.

On the other hand, the conventional surface coil having a diameter of 2.8 cm with RF shielding has a B ₁ penetration depth of 2.6 cm and a no-load Q value of 96.

B ₁ transmission is increased every time the W / H ratio is increased by 1. The penetration depth (2.4 cm) of B ₁ is always constant when W / H is 1 or more. When the ratio of W / H decreases, the no-load Q factor decreases because the radiation loss becomes large. At an optimization ratio of W / H, there is a balance between the B ₁ transmission and the no-load Q factor. When W / H was 1.5, 96% of the measured B ₁ penetration depth (2.3 cm) maximum was reached. In our study, we found that the optimum ratio of W / H of the microstrip-based receiver coil was 1.0 ~ 1.5.

4 shows a comparison of the distribution of signal intensities and B ₁ transmission measured by simulation in a phantom spaced vertically from a microstrip-based surface coil.

The Finite Difference Time Domain (FDTD) method is recorded in MATLAB Release 2009b (The Mathworks, Natick, Mass.) Where a workstation (Dual-core Intel Xeon 5200 processor with 1.86 GHz) This is applied for the numerical calculation of the depth presented by using the software.

This computer simulation is to construct a G10 (H = 2 mm) and double-turn winding microstrip coil as a substrate, with a dielectric constant of 80 with the same physical size coil used and an electrical conductivity of 0.5 S / m, .

The size of the box-shaped cell was 0.07 × 0.07 × 0.07 cm ³ and the electromagnetic wave was 65 time points per cycle. Calculations were made above 73,000 grid points. The B ₁ transmission depth is equal to a distance from the coil surface that is reduced by 5% of the maximum signal strength. A comparison of the B ₁ transmission between the simulation and the MRI experiment was made. The time required to run the simulation is less than 18 minutes.

4, the simulator was a B ₁ is transmitted through 2.52cm, single-turn shape and a double-transmission measurement the B ₁ in the microstrip coil turn shape were each 2.3cm and 2.43cm.

The highest B ₁ amplitude and signal intensity were found near the central surface of the phantom from the microstrip coil. The shape of B ₁ obtained using the double-turn coil is much more uniform than that obtained from the single-turn coil.

Next, an NMR signal and image acquisition of the thus-formed RF resonator will be described. FIG. 5 shows the FID (Free Induction Decay) of a phantom using a single-turn shape and a double-turn-shaped receive coil.

The 1-pulse NMR sequence is active-spun by the hard pulse at the Larmor frequency (43.9 MHz) and is adjusted to obtain the free induction decay (FID) of the gel phantom. And the microstrip RF receive coil is tuned to be obtained at the FID. The selection of the appropriate pulse width at a given power level is determined at the flip 90 spin.

The slope inversion of the FISP sequence uses phantom images by using MRI parameters (TR / TE 1,200 / 10 ms, factor matrix 128 × 128, FOV 10 × 10 cm ² , pixel size of 0.8 × 0.8 × 1.5 cm ³ , and 64 slices) It is used to acquire.

Referring to the drawing, two FIDs (red and green) have a phase of 90 degrees, and blue is a signal intensity. At 0.5 ms, the signal strength (15, 253) of the double-turn coil is greater than the signal strength of the single-turn coil.

Next, the SNR of the obtained image was examined. 6 shows an MR image of a gel phantom obtained from a surface-receiving coil of a single-turn shape and a double-turn shape. For single-size images, SNR was calculated using software provided in MATLAB. The signal S has a maximum uniform signal inside the phantom and is measured with an average intensity in a region of interest (ROI) of 10 x 10 pixels. Noise δ was evaluated for the standard deviation of the pixel intensity in the ROI of the same size located in the background area.

The SNR is calculated as follows.

The SNR (signal-to-noise ratio) of single-turn and double-turn RF receive coils compares the volume receive coil with a regular 2.8 cm diameter surface coil. Here, the ROI of the same size is selected in the MR image of the same slice.

Referring to FIG. 6, an MR image can be obtained using a single-turn (a) and double-turn (b) receive coil with a warped inverted version of the MR sequence of the FISP. Center slices 27 to 38 were displayed among 64 slices. The reason is that the rest of them do not have images of the gel phantom. The SNRs of the microstrip-based coil, the volume-receiving coil, and the coil having a diameter of 2.8 cm formed in the double-turn shape are 214 (占 16.7), 128 (占 .4), and 212 (占 .2).

FIG. 7 shows a normalized SNR shape of a gel phantom appearing in a center axis slice from left to right using a single-turn and double-turn microstrip coil and a volume-receiving coil. The images obtained from the double-turn RF reception coil have a uniform signal intensity as compared with those obtained from the single-turn reception coil. The SNR of the images obtained from the microstrip RF surface receive coil was much higher than that of the images obtained by the volume receive coil. On the other hand, in the figure, noise included in the center line is due to bubbles existing in the phantom.

The double-turn microstrip coil has a higher SNR than the single-turn coil. And the SNR of the microstrip coils having two different shapes is higher than that of the volume-receiving coil. The single-turn coil image intensity was unbalanced while the double-turn coil was balanced. The reason is that the non-uniform current density of the inner coil loop is compensated by the uniform current density of the outer coil loop. Thus, the double-turn microstrip RF receive coil is superior to the single-turn RF coil and the volume receive coil.

Although the no-load Q factor of a microstrip-based coil is higher than that of a conventional circular surface coil in the same crossing region, the SNR of a microstrip coil and a typical circular coil in this study is the same at 1T. Compared to conventional flat circular coils, the fabrication of surface-receiving coils based on the microstrip transmission line concept is simple and straightforward without RF shielding.

Therefore, a coil formed in a microstrip-based double-turn shape exhibits excellent characteristics as a surface-receiving coil used in a small-diameter low-magnetic field, so that it is simple, efficient, and useful in designing and implementing the coil.

Although the present invention has been described in detail with reference to specific embodiments thereof, it is to be understood that the present invention is not limited to the above-described embodiments, but various modifications may be made by those skilled in the art without departing from the scope of the present invention.

100: outer coil part
110: T-shaped incision
111: first incision groove
112: second incision groove
110a: first protrusion
110b: second projection
200: inner coil part
210:

Claims (6)

In a receive coil provided in a magnetic resonance imaging apparatus,
The receive coil
Wherein the outer coil portion and the inner coil portion are formed in a rectangular shape so as to be successively connected to each other,
Wherein a T-shaped incision is formed in the outer coil part from an outer center to an inner side of a rectangular one side, the T-shaped incision is formed in an area within 1/2 of the outer side of the coil width,
And a rounded portion is formed at an edge of the inner coil portion. A microstrip-based RF surface receiving coil for obtaining a magnetic resonance medical image.
delete delete The method according to claim 1,
Characterized in that the resonance wavelength of the receive coil is determined by the following equation: < EMI ID = 1.0 >

However, λ ₀ is the wavelength of light in free space,

Is an effective dielectric constant,

W is the width of the copper foil, and H is the thickness of the substrate.
The method according to claim 1,
Wherein the inner coil portion has a round or chamfered shape such that the gap between the outer coil portion and the inner coil portion in the edge region and the gap between the outer coil portion and the inner coil portion in the region of the side have different gap sizes And a microstrip-based RF surface-receiving coil for obtaining a magnetic resonance medical image.
A microstrip-based RF surface receiving coil for obtaining a magnetic resonance medical image according to any one of claims 1, 4, and 5,
A coaxial cable connected to an end of the receive coil,
A tolloid connected to the coaxial cable and compensating for the inductance of the coaxial cable,
And a tuning capacitance and a matching capacitance connected to the tolode.

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