METHOD AND SYSTEM FOR A UNIVERSAL NMR/MRI CONSOLE

• US 20140139216A1
• Filed: 05/28/2013
• Published: 05/22/2014
• Est. Priority Date: 11/21/2012
• Status: Active Grant

• Current Assignee: Aspect Imaging Ltd.
• Original Assignee: Aspect Imaging Ltd.
• Inventors: RAPOPORT, Uri
• Granted Patent: US 9,864,034 B2
• Time in Patent Office: Days
• US Class Current: 324/312
• CPC Class Codes: G01R 33/3607 RF waveform generators, e.g. frequency generators, amplitude-, frequency- or phase modulators or shifters, pulse programmers, digital to analog converters for the RF signal, means for filtering or attenuating of the RF signal
• CPC Class Codes: G01R 33/3852 Gradient amplifiers; means for controlling the application of a gradient magnetic field to the sample, e.g. a gradient signal synthesizer
• CPC Class Codes: G01R 33/54 Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console

Abstract

A method and system are provided for providing values for control signals for a pulsed magnetic resonance spectrometer such as an NMR spectrometer or an MRI apparatus. The AC output(s) corresponding to a particular signal (e.g. a magnetization or gradient pulse or pulse sequence) originating from a source spectrometer is measured and stored by an independent control unit. The digital output of the independent control unit is then connected to the digital input of the control electronics of a target pulsed magnetic resonance spectrometer, the value of the digital output varied until the AC output(s) of the appropriate signal source of the target spectrometer matches that of the corresponding output(s) of the source spectrometer, corrected, if necessary, for differences in magnetic field strengths.

Claims

1. A method for providing values for control signals for a pulsed magnetic resonance spectrometer, wherein said method comprises:

obtaining a source pulsed magnetic resonance spectrometer and associated control electronics characterized by m_s input channels and n_s output channels (“

source spectrometer”

), a target pulsed magnetic resonance spectrometer and associated control electronics characterized by m_t input channels and n_t output channels (“

target spectrometer”

), and an independent control device characterized by p input channels and q output channels capable of producing independent variable signals;

connecting at least one of said p input channels of said independent control device to at least one of said n_s output channels of said source spectrometer;

measuring at least one value of at least one output analog signal emitted by said control electronics of said source spectrometer when said control electronics are operating according to a predetermined pulse sequence;

storing said at least one value;

connecting at least one of said q output channels of said independent control device to at least one corresponding input of said target spectrometer;

providing at least one signal from said independent control device to said at least one input of the control electronics of said target spectrometer;

bringing at least one value of at least one analog output signal emitted by said control electronics of said target spectrometer to within a predetermined tolerance of a target value; and

,

storing at least one value of said signal output by said independent control device corresponding to the value of said signal output when said analog output signal from said target spectrometer is within said predetermined tolerance of said target value,

thereby providing a value for said signal provided by said independent control device to said target spectrometer required to produce a predetermined analog output signal.

2. The method according to claim 1, wherein said signal output from said independent control device is a digital signal, said output of said independent control device comprises digital output means for providing output of a digital signal, and said input of said target spectrometer comprises digital input means for accepting a digital signal.

3. The method according to claim 1, wherein a single instrument acts both as said source spectrometer and as said target spectrometer.

4. The method according to claim 1, wherein said source spectrometer and said target spectrometer are different instruments.

5. The method according to claim 1, wherein said pulsed magnetic resonance spectrometers are selected from the group consisting of FT-NMR spectrometers, FT-MRI spectrometers, FT-NQR spectrometers, and FT-EPR spectrometers.

6. The method according to claim 1, wherein said at least one value of said analog output signal is selected from the group consisting of voltage, current, duration, dead time between pulses, frequency, and intensity.

7. The method according to claim 1, wherein said analog output signal is selected from the group consisting of a signal directed to a probe coil, a gradient pulse, and a timing pulse.

8. The method according to claim 1, wherein said step of bringing at least one value of at least one analog output signal emitted by said control electronics of said target spectrometer to within a predetermined tolerance of a target value comprises:

sending at least one control signal of a predetermined value from said independent control device to said target spectrometer;

measuring at least one analog output produced by said target spectrometer in response to said digital signal; and

,

iteratively adjusting the value of said at least one control signal until said analog output is within a predetermined tolerance of said target value.

9. The method according to claim 1, further comprising:

repeating x times (x>

1) said steps following the first step of said method, each time providing a different signal from said independent control device;

storing each of said values at least one signal from said independent control device obtained after said step of bringing;

pairing each of said values of said signal from said independent control device with the corresponding analog output signal from said target spectrometer;

calculating a correlation between a value of said analog output signal of said target pulsed spectrometer and the value of said input signal from said independent control device necessary to produce said value; and

,

storing said correlation;

thereby providing means for calculating the value of an input signal to said target pulsed magnetic resonance spectrometer necessary to produce an arbitrary output signal.

10. The method according to claim 9, wherein, for each value of x:

said step of connecting at least one of said p input channels of said independent control device to at least of one of said n_s output channels of said source spectrometer comprises connecting y input channels toy output channels, 1<

y≦

p;

said step of connecting at least one of said q output channels of said independent control device to at least one corresponding input of said target spectrometer comprises connecting y output channels of said independent control device to y corresponding input channels of said target spectrometer;

said step of storing said at least one value comprises storing y values of said output signal, one for each output channel; and

,

said step of storing each of said values at least one signal from said independent control device comprises storing y values, one for each input channel;

thereby producing xy pairs of values.

11. The method according to claim 1, wherein said steps of storing are performed using digital storage means associated with said independent control device.

12. The method according to claim 1, wherein the time resolution of said independent control device is greater than that of any D/A converter in said control electronics of said source pulsed magnetic resonance spectrometer.

13. The method according to claim 1, further comprising:

providing a plurality of independent measuring means to said independent control device, each of said measuring means having a time resolution faster than that of said spectrometers;

measuring the value of at least one analog output of one of said spectrometers using at least two of said independent measuring means in turn; and

,

alerting an operator if at least one result of said step of measuring differs from at least one other result of said step of measuring by more than a predetermined tolerance.

14. An independent control unit for using analog output values from the control electronics of a source pulsed magnetic resonance spectrometer (“

source spectrometer”

) to provide values for control signals for a target pulsed magnetic resonance spectrometer (“

target spectrometer”

), wherein said independent control unit comprises;

a plurality p of input channels for accepting analog input signals from said source spectrometer;

signal measuring means for measuring parameters associated with said analog input signals;

a plurality q of output channels for directing control signals to said target spectrometer;

signal generating means for generating q independent output signals, each of said independent signals directed toward a separate output channel;

signal value storage means for storing values of said analog input signals and said output signals;

comparing means for comparing a measured value of an input signal with a stored value; and

,

calculating means for calculating a value of an output signal required to produce a predetermined output analog signal from said target spectrometer.

15. The independent control unit according to claim 14, wherein said signal generating means comprises digital signal generating means for generating digital signals.

16. The independent control unit according to claim 14, further comprising:

a plurality of signal value measuring means characterized by time resolutions faster than time resolutions of said spectrometers, said signal measuring means in connection with said input channels, for measuring values of signals in said input channels;

fast switching means for switching said connections between channels at a rate faster than the time resolution of a predetermined input source;

storage means for storing values measured by said signal measuring means; and

,

alerting means for alerting an operator if measurements made of the value of a predetermined channel by two of said signal value measuring means differ by a predetermined amount.

17. The independent control unit according to claim 16, wherein said signal value measuring means comprise A/D converters.