Testing device and testing method for multi-nuclear magnetic resonance radio frequency coil

Abstract

The invention discloses a testing device for a multi-nuclear magnetic resonance radio-frequency coil and a testing method for the multi-nuclear magnetic resonance radio-frequency coil, which are characterized in that an actual sample is replaced by a magnetic resonance signal generated after a tested sample is excited by a radio-frequency pulse and generated by simulation of a simulation MR signal generation source for testing; the cost can be reduced, the operation can be simplified, the dependence on a sample is reduced, the testing process is more controllable and repeatable, the performance of the tested radio frequency coil can be effectively optimized, and it is ensured that a high-quality image is obtained in the actual imaging process; the system can adapt to different imaging requirements and environmental conditions, and has different testing methods in different testing environments; the change-over switch is used for switching the test of transmitting and receiving, so that the transmitting function of the tested coil can be tested under the same test device, the receiving function of the tested radio frequency coil can also be tested, and the test efficiency is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic resonance imaging, and specifically relates to a testing device for a multi-nuclear magnetic resonance radio frequency coil, and also relates to a testing method for a multi-nuclear magnetic resonance radio frequency coil, which is suitable for completing the transmission function test and the receiving function test of the radio frequency coil under test through one scan, and can also measure and evaluate the transmission efficiency, receiving efficiency, and receiving sensitivity. Background Art

[0002] Magnetic resonance imaging (MRI) is a technology widely used in medical imaging, which can provide high-resolution soft tissue images. The basic principle of MRI is to use the nuclear magnetic resonance phenomenon. By applying a strong magnetic field and radio frequency (RF) pulses, the atomic nuclei in the sample resonate, thereby generating signals that can be used for imaging. The subsequently released signals (i.e., free induction decay signals) are captured by the receiving coil and converted into images. The performance of the RF coil directly affects the quality and accuracy of imaging, so the failure of the RF coil may result in reduced imaging quality or even failure to image.

[0003] The testing of multi-nuclear MRI RF coils in the prior art, whether on a MRI machine or on a workbench, usually relies on real samples. In some cases, especially when studying new imaging coils or testing RF coil performance, such as testing multi-nuclear MRI RF coils, the lack of suitable samples may lead to difficulties in imaging testing. The acquisition and processing of samples usually involve high costs, and the process of processing real samples often requires professional equipment and technicians, which also increases the complexity of the operation and a series of limitations such as time cost. For example, when conducting hyperpolarized xenon ( 129 When imaging Xe, it is usually necessary to perform hyperpolarization under specific conditions to improve 129 The signal strength of Xe, the production and storage cost of hyperpolarized xenon is high, if it is only for testing the performance of the coil, when multiple imaging tests are required, the overall cost increases significantly, and the acquisition process is complicated and time-consuming. 1 Compared with H 23 Na, 31 The magnetic moment and gyromagnetic ratio of atomic nuclei such as P are small and their content in the human body is low, so the magnetic resonance signal is weak. If the coil sensitivity is not high enough, the signal is often not collected, making the coil test difficult. 23 Na, 31 Therefore, it is very necessary to use the analog signal source to evaluate and optimize the performance of the multi-nuclear magnetic resonance RF coil. The coil can be tested without relying on real samples, which can reduce costs and simplify operations, improve test efficiency and repeatability, and provide a reference for the testing of multi-nuclear magnetic resonance RF coils.23 Na, 31 P and other multi-nuclear magnetic resonance radio frequency coil testing provides a new means. Summary of the invention

[0004] The purpose of the present invention is to address the above problems in the prior art and to provide a testing device for a multi-nuclear magnetic resonance radio frequency coil and a testing method for a multi-nuclear magnetic resonance radio frequency coil.

[0005] The above-mentioned purpose of the present invention is achieved by the following technical means:

[0006] A test device for a multi-nuclear magnetic resonance radio frequency coil comprises a radio frequency coil to be tested, a switching switch, an attenuator, a signal measurement module, an analog MR signal generator, a coaxial cable, and a small radio frequency probe. The radio frequency coil to be tested is provided with a coil connector, the small radio frequency probe is placed in a standard area of ​​the radio frequency coil to be tested, the switching switch comprises a control input port, a probe connection port, a radio frequency input port, and a radio frequency output port, the small radio frequency probe is connected to the probe connection port of the switching switch, the input end of the attenuator is connected to the radio frequency output port of the switching switch, the output end of the attenuator is connected to the input end of the signal measurement module, and the output end of the analog MR signal generator is connected to the radio frequency input port of the switching switch through a coaxial cable;

[0007] It also includes an acquisition module, which acquires the magnetic resonance signal received when the radio frequency coil under test is in a receiving state, obtains the received signal, and records and displays the waveform of the received signal;

[0008] The reference coil is used to replace the radio frequency coil under test to perform relative measurement of the radio frequency coil under test.

[0009] A method for testing a multi-nuclear magnetic resonance radio frequency coil, using the testing device for a multi-nuclear magnetic resonance radio frequency coil as described above, comprises the following steps:

[0010] Step 1: obtaining a transmission control signal and a radio frequency pulse signal, performing a transmission function test on the radio frequency coil under test, and determining whether the transmission function of the radio frequency coil under test is normal;

[0011] Step 2: Obtain a receiving control signal, perform a receiving function test on the radio frequency coil under test, and determine whether the receiving function of the radio frequency coil under test is normal;

[0012] Step 3: changing the pulse voltage VT0 of the radio frequency pulse signal, measuring the transmission efficiency of the radio frequency coil under test, replacing the radio frequency coil under test with the reference coil, and measuring the relative transmission efficiency of the radio frequency coil under test;

[0013] Step 4: Change the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator, measure the receiving efficiency and receiving sensitivity of the RF coil under test, replace the RF coil under test with the reference coil, and measure the relative receiving efficiency and relative receiving sensitivity of the RF coil under test.

[0014] As mentioned above, step 1 specifically includes the following steps:

[0015] Step 1.1, input the transmission control signal into the switching switch and the signal measurement module, and input the RF pulse signal into the RF coil under test. After the RF coil under test receives the RF pulse signal, the RF pulse signal excites the RF coil under test to generate a B1+ field signal. After the switching switch receives the transmission control signal, the probe connection port of the switching switch is connected to the RF output port, and the small RF probe is in a receiving state. The small RF probe receives the B1+ field signal emitted by the RF coil under test and inputs it into the signal measurement module. The signal measurement module displays and records the B1+ field signal waveform received by the small RF probe.

[0016] Step 1.2: Observe the B1+ field signal waveform to determine whether the transmitting function of the RF coil under test is normal, including: determining whether the amplitude change of the B1+ field signal waveform is within the set range, and whether the timing of the RF pulse signal waveform is consistent with the timing of the B1+ field signal waveform.

[0017] As mentioned above, step 2 specifically includes the following steps:

[0018] Step 2.1, inputting a receiving control signal into the switching switch and the analog MR signal generator, after the switching switch receives the receiving control signal, the probe connection port of the switching switch is connected to the RF input port, after the analog MR signal generator receives the receiving control signal, it simulates and generates a magnetic resonance signal, and transmits it to the small RF probe, and then receives the magnetic resonance signal radiated by the small RF probe through the RF coil under test, and then acquires the receiving signal through the acquisition module, and records and displays the receiving signal waveform;

[0019] Step 2.2: Analyze the received signal to determine whether the receiving function of the RF coil under test is normal: observe whether the received signal waveform has obvious distortion or irregular fluctuations, and check whether the amplitude and noise of the received signal waveform are within the set range.

[0020] The step 3 of measuring the transmission efficiency of the radio frequency coil under test specifically includes the following steps:

[0021] Step 3.1, change the pulse voltage VT0 of the RF pulse signal, repeat step 1.1, receive and display the B1+ field signal waveform through the signal measurement module, obtain the amplitude V1 of the B1+ field signal waveform according to the B1+ field signal waveform, and calculate the ratio V1 / VT0;

[0022] Step 3.2: Replace the RF coil under test with the reference coil, and then repeat step 3.1 to obtain the transmission efficiency of the reference coil, and then calculate the ratio of the transmission efficiency of the RF coil under test to that of the reference coil under the same test conditions.

[0023] Measuring the receiving sensitivity of the radio frequency coil under test in step 4 as described above specifically includes the following steps:

[0024] Step 4.1, changing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator, repeating step 2.1, the acquisition module acquires and displays the received signal waveform, obtains the amplitude VR1 of the received signal waveform, and calculates the ratio VR1 / VR0;

[0025] Step 4.2, reducing the amplitude VR0 of the magnetic resonance signal output by the analog MR signal generator, and obtaining the output amplitude VR0min of the analog MR signal generator corresponding to the minimum received signal that can be resolved by the acquisition module;

[0026] Step 4.3, replace the RF coil under test with the reference coil, and then repeat steps 4.1 and 4.2 to obtain the receiving efficiency of the reference coil, and then calculate the ratio of the receiving efficiency of the RF coil under test and the reference coil under the same test conditions, as well as the ratio of VR0min of the RF coil under test to VR0min of the reference coil.

[0027] A method for testing a multi-nuclear magnetic resonance radio frequency coil, when a magnetic resonance apparatus is used to generate a radio frequency pulse signal, transmit a control signal, and receive a control signal, further comprising a first signal adapter, the first signal adapter comprising an input port and three output ports, the input port of the first signal adapter being connected to a scanning bed of the magnetic resonance apparatus, the three output ports of the first signal adapter being respectively connected to a control input port of a switching switch, a signal measurement module, and a simulated MR signal generation source, the radio frequency coil to be tested being placed on the scanning bed of the magnetic resonance apparatus, and the radio frequency coil to be tested being connected to the scanning bed of the magnetic resonance apparatus;

[0028] The radio frequency pulse signal, the transmission control signal, and the reception control signal are generated by: running a pulse sequence on the magnetic resonance apparatus, when the pulse sequence runs in the transmission state, the magnetic resonance apparatus generates a radio frequency pulse signal, and the scanning bed of the magnetic resonance apparatus generates a transmission control signal; when the pulse sequence runs in the reception state, the scanning bed of the magnetic resonance apparatus generates a reception control signal;

[0029] The acquisition module is a magnetic resonance instrument. The radio frequency coil under test receives the magnetic resonance signal radiated by the small radio frequency probe and sends it to the magnetic resonance instrument through the coil connector. The magnetic resonance instrument acquires the received signal and records and displays the received signal waveform.

[0030] A testing method for a multi-nuclear magnetic resonance radio frequency coil, when a simulated transmitting and receiving control signal source is used to generate a transmitting control signal and a receiving control signal, and a radio frequency pulse source is used to generate a radio frequency pulse signal, the method further comprises a signal adapter board and a second signal adapter, the signal adapter board comprises a first input port, a second input port, a first output port, and a second bidirectional port, the second signal adapter comprises a first output port, a second output port, a third output port, a fourth output port, and a fifth output port, the first input port of the signal adapter board is connected to the output port of the radio frequency pulse source, the second input port of the signal adapter board is connected to the output port of the simulated transmitting and receiving control signal source, the first output port of the signal adapter board is connected to the first input port of the second signal adapter, the second bidirectional port of the signal adapter board is connected to the coil connector, the first output port of the second signal adapter is connected to the control input port of the switching switch, the second output port of the second signal adapter is connected to a signal measurement module, the third output port of the second signal adapter is connected to a simulated MR signal generation source, the fourth output port of the second signal adapter is connected to the radio frequency pulse source, and the fifth output port of the second signal adapter is connected to an independent signal input channel of the signal measurement module;

[0031] The radio frequency pulse signal, the transmission control signal, and the receiving control signal are generated in the following manner: the simulation transmission and receiving control signal source simulates the generation of the transmission control signal, and sends the transmission control signal to the switching switch, the signal measurement module, and the radio frequency pulse source, and the radio frequency pulse source generates a radio frequency pulse signal after receiving the transmission control signal; the simulation transmission and receiving control signal source simulates the generation of the receiving control signal;

[0032] The acquisition module is a signal measurement module. The RF coil under test receives the magnetic resonance signal radiated by the small RF probe and then transmits it to the signal adapter board and then to the signal measurement module through the second signal adapter. The signal measurement module acquires the received signal and records and displays the received signal waveform.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The present invention uses an analog MR signal generator to emit analog signals to replace actual samples for testing, which not only reduces costs and simplifies operations, reduces dependence on samples, but also makes the testing process more controllable and repeatable. The present invention can effectively optimize the performance of the RF coil under test and ensure that high-quality images are obtained during the actual imaging process.

[0035] (2) The present invention can adapt to different imaging requirements and environmental conditions, and has different testing methods in different testing environments.

[0036] (3) The present invention uses a switching switch to switch between the transmission and reception tests, so that the transmission function of the radio frequency coil under test can be tested, and the reception function of the radio frequency coil under test can also be tested under the same test device, thereby improving the test efficiency.

[0037] (4) The present invention can complete the transmission function test and the receiving function test of the radio frequency coil under test through one scan, and has a simple structure, convenient operation and strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the circuit structure of the device of Example 1 of the present invention;

[0039] Figure 2 Schematic diagram of the circuit structure of using a magnetic resonance apparatus to complete the test of the radio frequency coil under test in Embodiment 2 of the present invention;

[0040] Figure 3 It is a schematic diagram of the circuit structure of using a radio frequency pulse source and a simulated transmission and reception control signal source to complete the test of the radio frequency coil under test on a workbench in embodiment 3 of the present invention;

[0041] Reference numerals and corresponding component names:

[0042] 10—magnetic resonance apparatus; 102—working table; 103—radio frequency pulse source; 104—analog transmission and reception control signal source; 105—signal adapter board; 20—scanning bed; 21—first signal adapter; 22—second signal adapter; 30—coil connector; 40—radio frequency coil under test; 50—small radio frequency probe; 60—switching switch; 70—attenuator; 80—signal measurement module; 90—analog MR signal generator; 100—coaxial cable. DETAILED DESCRIPTION

[0043] In order to facilitate those skilled in the art to understand and implement the present invention, the present invention is further described in detail below in conjunction with embodiments. The embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0044] Embodiment 1:

[0045] A testing device for a multi-nuclear magnetic resonance radio frequency coil comprises a switching switch 60, an attenuator 70, a signal measuring module 80, an analog MR signal generator (analog magnetic resonance signal generator) 90, a coaxial cable 100, a small radio frequency probe 50, and a radio frequency coil 40 to be tested. The radio frequency coil 40 to be tested is provided with a coil connector 30. The small radio frequency probe 50 is placed in a standard area of ​​the radio frequency coil 40 to be tested (such as placed in the center of the radio frequency coil 40 to be tested). The switching switch 60 comprises a control input port, a probe connection port, a radio frequency input port, and a radio frequency output port. The small radio frequency probe 50 is connected to the probe connection port of the switching switch 60. The input end of the attenuator 70 is connected to the radio frequency output port of the switching switch 60. The output end of the attenuator 70 is connected to the input end of the signal measuring module 80. The output end of the analog MR signal generator 90 is connected to the radio frequency input port of the switching switch 60 through the coaxial cable 100.

[0046] The switch 60 is used to receive a transmission control signal or a reception control signal, and switches the small RF probe 50 to a transmission state or a reception state according to the received transmission control signal or the reception control signal, corresponding to the switching of the reception state and the transmission state of the RF coil 40 under test.

[0047] The small RF probe 50 (smaller than the RF coil 40 under test, convenient for placement within the standard area of ​​the RF coil 40 under test) is used to receive the signal generated by the RF coil 40 under test. The small RF probe 50 can be implemented using a small RF coil (RF coil) or a small antenna.

[0048] The attenuator 70 is used to adjust the signal strength to ensure the stability and reliability of the signal.

[0049] The signal measurement module 80 can use an oscilloscope, a spectrum analyzer, or other general measuring instruments and special measuring devices to monitor and analyze the received signal. The signal measurement module 80 is used to observe the transmission state of the RF coil 40 under test, and the reception state of the RF coil 40 under test. Before using the signal measurement module 80 for measurement, the signal measurement module 80 needs to be calibrated to ensure the accuracy of the collected signal.

[0050] The simulated MR signal generator 90 is used to simulate the magnetic resonance signal generated by the sample under test after being excited by the radio frequency pulse signal.

[0051] When the transmission function test of the RF coil 40 under test is performed, the switching switch 60 and the signal measurement module 80 receive the transmission control signal, the probe connection port of the switching switch 60 is connected to the RF output port, and the probe connection port of the switching switch 60 is disconnected from the RF input port, the small RF probe 50 is in the receiving state, and the transmission control signal is used as the waveform capture trigger signal of the signal measurement module 80.

[0052] When the receiving function test of the RF coil 40 under test is performed, the switching switch 60 and the simulated MR signal generator 90 receive a receiving control signal, the probe connection port of the switching switch 60 is connected to the RF input port, and the probe connection port is disconnected from the RF output port. The small RF probe 50 is in a transmitting state, and the receiving control signal is used as an output trigger of the simulated MR signal generator 90. The simulated MR signal generator 90 simulates and generates a magnetic resonance signal that is transmitted to the small RF probe 50, and the RF coil 40 under test receives the magnetic resonance signal transmitted to the small RF probe 50.

[0053] It also includes an acquisition module, which is used to acquire the magnetic resonance signal received when the radio frequency coil 40 under test is in a receiving state, thereby obtaining a received signal, and recording and displaying the received signal waveform;

[0054] The device of the present invention can be used on the magnetic resonance apparatus 10 and the workbench 102 respectively.

[0055] A reference coil is also included. Relative measurements (such as relative transmission efficiency, relative receiving efficiency, and relative receiving sensitivity) of the RF coil 40 under test can be performed by replacing the RF coil 40 under test with the reference coil.

[0056] Embodiment 2:

[0057] A method for testing a multi-nuclear magnetic resonance radio frequency coil, using the testing device for a multi-nuclear magnetic resonance radio frequency coil described in the first embodiment, in this embodiment, a magnetic resonance apparatus 10 is used to complete the test of the radio frequency coil 40 under test, and further includes a first signal adapter 21, including the following steps:

[0058] The device of the present invention is connected to the magnetic resonance apparatus 10 in the following manner: the first signal adapter 21 includes an input port and three output ports, the input port of the first signal adapter 21 is connected to the scanning bed 20 of the magnetic resonance apparatus 10, and the three output ports of the first signal adapter 21 are respectively connected to the control input port of the switching switch 60, the signal measurement module 80, and the analog MR signal generator 90.

[0059] The first signal adapter 21 is used to output the transmission control signal to the switch 60 and the signal measurement module 80 , and to output the reception control signal to the switch 60 and the analog MR signal generator 90 .

[0060] Before the measurement, the operating frequency of the RF coil 40 to be measured is adjusted to below the corresponding resonant frequency. The coil resonant frequency is based on the following formula: For example, the resonant frequency of 129Xe at 3T (Tesla, the unit of magnetic induction intensity) is 35.49MHz, where ω is the resonant frequency of the RF coil 40 under test, L is the inductance of the RF coil 40 under test, and CT The RF coil 40 under test is tuned to a capacitance of the RF coil 40 under test. The RF coil 40 under test is then connected to the scanning bed 20 through the coil connector 30 and placed on the scanning bed 20 . The small RF probe 50 is placed in the standard region of the RF coil 40 under test.

[0061] In this embodiment, the magnetic resonance apparatus 10 is used to generate a transmission control signal, a reception control signal, a radio frequency pulse signal, and as an acquisition module to acquire a magnetic resonance signal received when the radio frequency coil 40 under test is in a receiving state, obtain a reception signal, and record and display the reception signal waveform;

[0062] Step 1: Run a pulse sequence on the magnetic resonance apparatus 10. When the pulse sequence is in the transmitting state, perform a transmitting function test on the radio frequency coil 40 under test, and determine whether the transmitting function of the radio frequency coil 40 under test is normal. Specifically, the following steps are included:

[0063] Step 1.1, when the pulse sequence is running in the transmitting state, the magnetic resonance apparatus 10 generates a radio frequency pulse signal, the first signal adapter 21 extracts the transmitting control signal from the scanning bed 20 of the magnetic resonance apparatus 10, and sends it to the switching switch 60 and the signal measurement module 80 respectively, the radio frequency coil 40 under test receives the radio frequency pulse signal, and the radio frequency pulse signal excites the radio frequency coil 40 under test to generate a B1+ field (radio frequency field) signal, after the switching switch 60 receives the transmitting control signal, the probe connection port of the switching switch 60 and the radio frequency output port are connected, the small radio frequency probe 50 is in the receiving state, and the small radio frequency probe 50 receives the B1+ field signal emitted by the radio frequency coil 40 under test and then inputs it into the signal measurement module 80 through the switching switch 60 and the attenuator 70, and the signal measurement module 80 displays and records the waveform of the B1+ field signal received by the small radio frequency probe 50;

[0064] Step 1.2, observe the B1+ field signal waveform to determine whether the transmitting function of the RF coil 40 under test is normal, including: determining whether the amplitude change of the B1+ field signal waveform is within the set range, and whether the timing of the RF pulse signal waveform is consistent with the timing of the B1+ field signal waveform.

[0065] Step 2: When the pulse sequence is running in the receiving state, the receiving function test of the RF coil 40 under test is performed to determine whether the receiving function of the RF coil 40 under test is normal, which specifically includes the following steps:

[0066] Step 2.1, when the pulse sequence is running in the receiving state, the first signal adapter 21 extracts the receiving control signal from the scanning bed 20 interface of the magnetic resonance apparatus 10, and sends it to the switching switch 60 and the analog MR signal generator 90 respectively. After the switching switch 60 receives the receiving control signal, the probe connection port of the switching switch 60 and the RF input port are connected, and the small RF probe 50 is in the transmitting state. After receiving the receiving control signal, the analog MR signal generator 90 simulates the magnetic resonance signal generated by the sample under test after the RF pulse excitation, and transmits it to the small RF probe 50. Then, the RF coil 40 under test receives the magnetic resonance signal radiated by the small RF probe 50 and then sends it to the magnetic resonance apparatus 10 through the coil connector 30. The magnetic resonance apparatus 10 collects the receiving signal, and records and displays the receiving signal waveform.

[0067] Step 2.2: Analyze the received signal to determine whether the receiving function of the RF coil 40 under test is normal, including: observing whether the received signal waveform has obvious distortion or irregular fluctuations, and checking and analyzing whether the amplitude and noise of the received signal waveform are within the set range.

[0068] Step 3: change the pulse voltage VT0 of the pulse sequence (i.e., the pulse voltage of the radio frequency pulse signal generated by the magnetic resonance apparatus 10), and then run the pulse sequence. When the pulse sequence runs in the transmitting state, measure the transmission efficiency of the radio frequency coil 40 under test, replace the radio frequency coil 40 under test with the reference coil, and measure the relative transmission efficiency of the radio frequency coil 40 under test. Specifically, the following steps are included:

[0069] Step 3.1, when the pulse sequence is running in the transmitting state, repeat step 1.1, the signal measurement module 80 receives and displays the B1+ field signal waveform, obtains the amplitude V1 of the B1+ field signal waveform according to the B1+ field signal waveform, and calculates the ratio V1 / VT0, which is used to evaluate the transmission efficiency of the RF coil 40 under test;

[0070] Step 3.2, replace the RF coil 40 under test with the reference coil, and then repeat step 3.1 to obtain the transmission efficiency of the reference coil, and then calculate the ratio of the transmission efficiency of the RF coil 40 under test and the reference coil under the same test conditions, so as to evaluate the relative transmission efficiency of the RF coil 40 under specific test conditions.

[0071] Step 4: when the pulse sequence is running in the receiving state, the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator 90 is changed, the receiving efficiency and receiving sensitivity of the RF coil 40 under test are measured, the RF coil 40 under test is replaced with a reference coil, and the relative receiving efficiency and relative receiving sensitivity of the RF coil 40 under test are measured, which specifically includes the following steps:

[0072] Step 4.1, when the pulse sequence is running in the receiving state, the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator 90 is changed, and step 2.1 is repeated, the magnetic resonance apparatus 10 collects and displays the received signal waveform, obtains the amplitude VR1 of the received signal waveform, and calculates the ratio VR1 / VR0, VR1 / VR0 is used to evaluate the receiving efficiency of the radio frequency coil 40 under test;

[0073] Step 4.2, reducing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator 90, and obtaining the output amplitude VR0min of the simulated MR signal generator 90 corresponding to the minimum received signal that can be resolved by the magnetic resonance apparatus 10, VR0min is used to evaluate the receiving sensitivity of the RF coil 40 under specific test conditions;

[0074] Step 4.3, replace the RF coil 40 under test with the reference coil, and then repeat steps 4.1 and 4.2 to obtain the receiving efficiency of the reference coil, and then calculate the ratio of the receiving efficiency of the RF coil 40 under test and the reference coil under the same test conditions, as well as the ratio of VR0min of the RF coil 40 under test and VR0min of the reference coil, to evaluate the relative receiving efficiency and relative receiving sensitivity of the RF coil 40 under the same test conditions.

[0075] When the magnetic resonance apparatus 10 is used, the transmission function test and the reception function test of the radio frequency coil 40 under test can be completed simultaneously when a pulse sequence scan is run on the magnetic resonance apparatus 10 .

[0076] Embodiment 3:

[0077] A method for testing a multi-nuclear magnetic resonance radio frequency coil, using the testing device for a multi-nuclear magnetic resonance radio frequency coil described in the above embodiment 1, in this embodiment, a radio frequency pulse source 103 and a simulated transmission and reception control signal source 104 are used to complete the test of the radio frequency coil 40 under test on a workbench 102, and also includes a signal adapter board 105 and a second signal adapter 22, including the following steps:

[0078] The device of the present invention is connected to the radio frequency pulse source 103 and the analog transmission and reception control signal source 104 in the following manner:

[0079] The signal adapter board 105 includes two input ports and two output ports, namely, a first input port, a second input port, a first output port, and a second bidirectional port. The second signal adapter 22 includes one input port and five output ports, namely, a first output port, a second output port, a third output port, a fourth output port, and a fifth output port. The first input port of the signal adapter board 105 is connected to the output port of the RF pulse source 103, the second input port of the signal adapter board 105 is connected to the output port of the analog transmission and reception control signal source 104, and the first output port of the signal adapter board 105 is connected to the output port of the analog transmission and reception control signal source 104. The output port is connected to the first input port of the second signal adapter 22, the second bidirectional port of the signal adapter board 105 is connected to the coil connector 30, the first output port of the second signal adapter 22 is connected to the control input port of the switching switch 60, the second output port of the second signal adapter 22 is connected to the signal measurement module 80, the third output port of the second signal adapter 22 is connected to the analog MR signal generator 90, the fourth output port of the second signal adapter 22 is connected to the RF pulse source 103, and the fifth output port of the second signal adapter 22 is connected to the independent signal input channel of the signal measurement module 80.

[0080] In this embodiment, the signal measurement module 80 is used to display and record the B1+ field signal waveform and the transmission control signal waveform received by the small RF probe 50, and also serves as an acquisition module to acquire the magnetic resonance signal received when the RF coil 40 under test is in the receiving state, obtain the received signal, and record and display the received signal waveform;

[0081] The RF pulse source 103 is used to simulate and generate RF pulse signals, and provide the signals to the RF coil 40 under test for transmitting function testing.

[0082] The simulated transmission and reception control signal source 104 is used to simulate a transmission control signal or a reception control signal.

[0083] The first input port of the second signal adapter 22 is used to obtain the analog transmission control signal or the reception control signal, and the reception signal from the RF coil 40 under test. The transmission control signal or the reception control signal is divided into five paths through the splitter in the second signal adapter 22. One path is input to the switching switch 60 through the first output port to switch the transmission state or the reception state of the small RF probe 50; one path is input to the signal measurement module 80 through the second output port as a waveform capture trigger signal; one path is input to the analog MR signal generator 90 through the third output port for output triggering; and one path is input to the RF pulse source 103 through the fourth output port as a trigger signal. In addition, the reception signal of the RF coil 40 under test is input to the independent signal input channel of the signal measurement module 80 through the fifth output port for collection and analysis.

[0084] Before the measurement, it is also necessary to adjust the operating frequency of the RF coil 40 to be measured to below the corresponding resonance frequency, and place the small RF probe 50 in the standard area of ​​the RF coil 40 to be measured.

[0085] Step 1, simulate the transmission and reception control signal source 104 to simulate the generation of the transmission control signal, and after the RF pulse source 103 receives the transmission control signal, the RF pulse source 103 generates a RF pulse signal to test the transmission function of the RF coil 40 under test, and determine whether the transmission function of the RF coil 40 under test is normal, which specifically includes the following steps:

[0086] Step 1.1, the simulation transmission and reception control signal source 104 simulates the generation of the transmission control signal, and sends the transmission control signal to the switching switch 60, the signal measurement module 80, and the RF pulse source 103 through the second signal adapter 22. After the RF pulse source 103 receives the transmission control signal, the RF pulse source 103 generates a RF pulse signal; the RF coil 40 under test receives the RF pulse signal, and the RF pulse signal excites the RF coil 40 under test to generate a B1+ field signal. After receiving the transmission control signal, the switching switch 60 connects the probe connection port and the RF output port, and the small RF probe 50 is in a receiving state. The small RF probe 50 receives the B1+ field signal emitted by the RF coil 40 under test and inputs it into the signal measurement module 80. The signal measurement module 80 displays and records the B1+ field signal waveform received by the small RF probe 50;

[0087] Step 1.2, observe the B1+ field signal waveform to determine whether the transmitting function of the RF coil 40 under test is normal, including: determining whether the amplitude change of the B1+ field signal waveform is within a set range, and whether the timing of the RF pulse signal waveform is consistent with the timing of the B1+ field signal waveform.

[0088] Step 2: The simulated transmission and reception control signal source 104 simulates and generates a reception control signal to test the reception function of the RF coil 40 under test and determine whether the reception function of the RF coil 40 under test is normal. Specifically, the following steps are included:

[0089] Step 2.1, the simulated transmission and reception control signal source 104 simulates the generation of a reception control signal, and sends the reception control signal to the switching switch 60 and the simulated MR signal generator 90 through the second signal adapter 22. After receiving the reception control signal, the switching switch 60 connects the probe connection port and the RF input port, and the small RF probe 50 is in the transmitting state. After receiving the reception control signal, the simulated MR signal generator 90 simulates the generation of the magnetic resonance signal of the sample under test after RF pulse excitation, and transmits it to the small RF probe 50. Then, the magnetic resonance signal radiated by the small RF probe 50 is received by the RF coil 40 under test, and then transmitted to the signal adapter board 105, and then sent to the signal measurement module 80 through the second signal adapter 22. The signal measurement module 80 collects the reception signal, and records and displays the reception signal waveform.

[0090] Step 2.2: Analyze the received signal to determine whether the receiving function of the RF coil 40 under test is normal: observe whether the received signal waveform has obvious distortion or irregular fluctuations, and check and analyze whether the amplitude and noise of the received signal waveform are within the set range.

[0091] Step 3: changing the pulse voltage VT0 of the radio frequency pulse output by the radio frequency pulse source 103, measuring the transmission efficiency of the radio frequency coil 40 under test, replacing the radio frequency coil 40 under test with a reference coil, and measuring the relative transmission efficiency of the radio frequency coil 40 under test, specifically including the following steps:

[0092] Step 3.1, changing the pulse voltage VT0 of the RF pulse output by the RF pulse source 103, repeating step 1.1, the signal measurement module 80 receives and displays the B1+ field signal waveform, obtains the amplitude V1 of the B1+ field signal waveform according to the B1+ field signal waveform, calculates the ratio V1 / VT0, and V1 / VT0 is used to evaluate the transmission efficiency of the RF coil 40 under test;

[0093] Step 3.2, replace the RF coil 40 under test with the reference coil, and then repeat step 3.1 to obtain the transmission efficiency of the reference coil, and then calculate the ratio of the transmission efficiency of the RF coil 40 under test and the reference coil under the same test conditions, so as to evaluate the relative transmission efficiency of the RF coil 40 under specific test conditions.

[0094] Step 4: changing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator 90, measuring the receiving efficiency and receiving sensitivity of the RF coil 40 under test, replacing the RF coil 40 under test with the reference coil, and measuring the relative receiving efficiency and relative receiving sensitivity of the RF coil 40 under test, specifically including the following steps:

[0095] Step 4.1, changing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator 90, repeating step 2.1, the signal measurement module 80 collects and displays the received signal waveform, obtains the amplitude VR1 of the received signal waveform, and calculates the ratio VR1 / VR0, VR1 / VR0 is used to evaluate the receiving efficiency of the radio frequency coil 40 under test;

[0096] Step 4.2, reducing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator 90, and obtaining the output amplitude VR0min of the simulated MR signal generator 90 corresponding to the minimum received signal that can be resolved by the signal measurement module 80, VR0min is used to evaluate the receiving sensitivity of the RF coil 40 under specific test conditions;

[0097] Step 4.3, replace the RF coil 40 under test with the reference coil, and then repeat steps 4.1 and 4.2 to obtain the receiving efficiency of the reference coil, and then calculate the ratio of the receiving efficiency of the RF coil 40 under test and the reference coil under the same test conditions and the ratio of VR0min of the RF coil 40 under test and VR0min of the reference coil, so as to evaluate the relative receiving efficiency and relative receiving sensitivity of the RF coil 40 under the same test conditions.

[0098] The transmission function test and the receiving function test of the radio frequency coil 40 under test can be completed simultaneously by performing one simulation scan on the workbench 102 .

[0099] In addition, in the above-mentioned embodiments 1 and 2, the receiving efficiency is defined as the ratio of the signal amplitude received by the RF coil 40 under test to the output amplitude of the analog MR signal source; the receiving sensitivity is defined as the output amplitude of the analog MR signal source corresponding to the minimum received signal that can be resolved by the RF coil 40 under test.

[0100] It should be noted that the embodiments described in the present invention are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the described embodiments or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the attached claims.

Claims

1. A test device for a multi-nuclear magnetic resonance radio frequency coil, comprising a radio frequency coil to be tested (40), characterized in that: The device also comprises a switching switch (60), an attenuator (70), a signal measurement module (80), a simulated MR signal generator (90), a coaxial cable (100), a small radio frequency probe (50), and a reference coil. The radio frequency coil (40) under test is provided with a coil connector (30). The small radio frequency probe (50) is placed in the standard area of ​​the radio frequency coil (40) under test. The switching switch (60) comprises a control input port, a probe connection port, a radio frequency input port, and a radio frequency output port. The small radio frequency probe (50) is connected to the probe connection port of the switching switch (60). The input end of the attenuator (70) is connected to the radio frequency output port of the switching switch (60). The output end of the attenuator (70) is connected to the input end of the signal measurement module (80). The output end of the simulated MR signal generator (90) is connected to the radio frequency input port of the switching switch (60) through the coaxial cable (100). It also includes a collection module, which collects the magnetic resonance signal received when the radio frequency coil (40) under test is in a receiving state, obtains the received signal, and records and displays the received signal waveform; The reference coil replaces the radio frequency coil (40) under test to perform relative measurement of the radio frequency coil (40) under test.

2. A method for testing a multi-nuclear magnetic resonance radio frequency coil, using the testing device for a multi-nuclear magnetic resonance radio frequency coil according to claim 1, characterized in that: The following steps are involved: Step 1: acquiring a transmission control signal and a radio frequency pulse signal, performing a transmission function test on the radio frequency coil (40) under test, and determining whether the transmission function of the radio frequency coil (40) under test is normal; Step 2: obtaining a receiving control signal, performing a receiving function test on the radio frequency coil (40) under test, and determining whether the receiving function of the radio frequency coil (40) under test is normal; Step 3: changing the pulse voltage VT0 of the radio frequency pulse signal, measuring the transmission efficiency of the radio frequency coil (40) under test, replacing the radio frequency coil (40) under test with a reference coil, and measuring the relative transmission efficiency of the radio frequency coil (40) under test; Step 4: changing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator (90), measuring the receiving efficiency and receiving sensitivity of the radio frequency coil (40) under test, replacing the radio frequency coil (40) under test with a reference coil, and measuring the relative receiving efficiency and relative receiving sensitivity of the radio frequency coil (40) under test.

3. A method for testing a multi-nuclear magnetic resonance radio frequency coil according to claim 2, characterized in that: The step 1 specifically comprises the following steps: Step 1.1, inputting a transmission control signal into the switching switch (60) and the signal measuring module (80), and inputting a radio frequency pulse signal into the radio frequency coil (40) under test, after the radio frequency coil (40) under test receives the radio frequency pulse signal, the radio frequency pulse signal excites the radio frequency coil (40) under test to generate a B1+ field signal, after the switching switch (60) receives the transmission control signal, the probe connection port of the switching switch (60) and the radio frequency output port are connected, the small radio frequency probe (50) is in a receiving state, the small radio frequency probe (50) receives the B1+ field signal emitted by the radio frequency coil (40) under test and inputs it into the signal measuring module (80), the signal measuring module (80) displays and records the waveform of the B1+ field signal received by the small radio frequency probe (50); Step 1.2, observing the B1+ field signal waveform to determine whether the transmitting function of the radio frequency coil (40) under test is normal, including: determining whether the amplitude change of the B1+ field signal waveform is within a set range, and whether the timing of the radio frequency pulse signal waveform is consistent with the timing of the B1+ field signal waveform.

4. A method for testing a multi-nuclear magnetic resonance radio frequency coil according to claim 3, characterized in that: The step 2 specifically includes the following steps: Step 2.1, inputting a receiving control signal into the switching switch (60) and the analog MR signal generator (90), and after the switching switch (60) receives the receiving control signal, the probe connection port of the switching switch (60) and the radio frequency input port are connected, and after the analog MR signal generator (90) receives the receiving control signal, it simulates and generates a magnetic resonance signal, and transmits it to the small radio frequency probe (50), and then receives the magnetic resonance signal radiated by the small radio frequency probe (50) through the radio frequency coil under test (40), and then acquires the received signal through the acquisition module, and records and displays the received signal waveform; Step 2.2: Analyze the received signal to determine whether the receiving function of the radio frequency coil (40) under test is normal: observe whether the received signal waveform has obvious distortion or irregular fluctuations, and check whether the amplitude and noise of the received signal waveform are within the set range.

5. A method for testing a multi-nuclear magnetic resonance radio frequency coil according to claim 4, characterized in that: The step 3 of measuring the transmission efficiency of the radio frequency coil (40) under test specifically comprises the following steps: Step 3.1, changing the pulse voltage VT0 of the radio frequency pulse signal, repeating step 1.1, receiving and displaying the B1+ field signal waveform through the signal measurement module (80), obtaining the amplitude V1 of the B1+ field signal waveform according to the B1+ field signal waveform, and calculating the ratio V1 / VT0; Step 3.2, replace the radio frequency coil (40) under test with the reference coil, and then repeat step 3.1 to obtain the transmission efficiency of the reference coil, and then calculate the ratio of the transmission efficiency of the radio frequency coil (40) under test to that of the reference coil under the same test conditions.

6. A method for testing a multi-nuclear magnetic resonance radio frequency coil according to claim 5, characterized in that: The step 4 of measuring the receiving sensitivity of the radio frequency coil (40) under test specifically comprises the following steps: Step 4.1, changing the amplitude VR0 of the magnetic resonance signal output by the simulated MR signal generator (90), repeating step 2.1, the acquisition module acquires and displays the received signal waveform, obtains the amplitude VR1 of the received signal waveform, and calculates the ratio VR1 / VR0; Step 4.2, reducing the amplitude VR0 of the magnetic resonance signal output by the analog MR signal generator (90), and obtaining the output amplitude VR0min of the analog MR signal generator (90) corresponding to the minimum received signal that can be resolved by the acquisition module; Step 4.3, replace the radio frequency coil under test (40) with the reference coil, and then repeat steps 4.1 and 4.2 to obtain the receiving efficiency of the reference coil, and then calculate the ratio of the receiving efficiency of the radio frequency coil under test (40) and the reference coil under the same test conditions, and the ratio of VR0min of the radio frequency coil under test (40) to VR0min of the reference coil.

7. A method for testing a multi-nuclear magnetic resonance radio frequency coil according to claim 6, characterized in that: When a magnetic resonance apparatus (10) is used to generate radio frequency pulse signals, transmit control signals, and receive control signals, the device further comprises a first signal adapter (21), the first signal adapter (21) comprising an input port and three output ports, the input port of the first signal adapter (21) being connected to a scanning bed (20) of the magnetic resonance apparatus (10), the three output ports of the first signal adapter (21) being connected to a control input port of a switch (60), a signal measurement module (80), and a simulated MR signal generation source (90), respectively, the radio frequency coil (40) to be tested being placed on the scanning bed (20) of the magnetic resonance apparatus (10), and the radio frequency coil (40) to be tested being connected to the scanning bed (20) of the magnetic resonance apparatus (10); The radio frequency pulse signal, the transmission control signal, and the reception control signal are generated in the following manner: a pulse sequence is run on the magnetic resonance apparatus (10); when the pulse sequence is run in a transmission state, the magnetic resonance apparatus (10) generates a radio frequency pulse signal, and a scanning bed (20) of the magnetic resonance apparatus (10) generates a transmission control signal; when the pulse sequence is run in a reception state, the scanning bed (20) of the magnetic resonance apparatus (10) generates a reception control signal; The acquisition module is a magnetic resonance instrument (10). The radio frequency coil (40) under test receives the magnetic resonance signal radiated by the small radio frequency probe (50) and sends it to the magnetic resonance instrument (10) through the coil connector (30). The magnetic resonance instrument (10) acquires the received signal and records and displays the received signal waveform.

8. The method for testing a multi-nuclear magnetic resonance radio frequency coil according to claim 6, characterized in that: When an analog transmission and reception control signal source (104) is used to generate a transmission control signal and a reception control signal, and an RF pulse source (103) is used to generate an RF pulse signal, a signal adapter board (105) and a second signal adapter (22) are also included. The signal adapter board (105) includes a first input port, a second input port, a first output port, and a second bidirectional port. The second signal adapter (22) includes a first output port, a second output port, a third output port, a fourth output port, and a fifth output port. The first input port of the signal adapter board (105) is connected to the output port of the RF pulse source (103). The second input port of the signal adapter board (105) is connected to the output port of the analog transmission and reception control signal source (104). The first output port of the signal adapter board (105) is connected to the first input port of the second signal adapter (22), the second bidirectional port of the signal adapter board (105) is connected to the coil connector (30), the first output port of the second signal adapter (22) is connected to the control input port of the switch (60), the second output port of the second signal adapter (22) is connected to the signal measurement module (80), the third output port of the second signal adapter (22) is connected to the simulated MR signal source (90), the fourth output port of the second signal adapter (22) is connected to the radio frequency pulse source (103), and the fifth output port of the second signal adapter (22) is connected to the independent signal input channel of the signal measurement module (80); The radio frequency pulse signal, the transmission control signal, and the reception control signal are generated in the following manner: the simulation transmission and reception control signal source (104) simulates the generation of the transmission control signal, and sends the transmission control signal to the switch (60), the signal measurement module (80), and the radio frequency pulse source (103); after the radio frequency pulse source (103) receives the transmission control signal, the radio frequency pulse source (103) generates a radio frequency pulse signal; The analog transmission and reception control signal source (104) simulates and generates a reception control signal; The acquisition module is a signal measurement module (80). The radio frequency coil (40) under test receives the magnetic resonance signal radiated by the small radio frequency probe (50), transmits the signal to the signal adapter board (105), and then sends the signal to the signal measurement module (80) through the second signal adapter (22). The signal measurement module (80) acquires the received signal, and records and displays the received signal waveform.

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