Method and apparatus for magnetic resonance imaging
In a method and apparatus for magnetic resonance imaging, in order to create a T1 map, an pulse sequence is used that includes at least one exposure cycle, wherein the exposure cycle includes an inversion pulse, a saturation pulse quantity of one or more saturation pulses and a readout step quantity of one or more readout steps. Within the exposure cycle, at least one saturation pulse of the saturation pulse quantity follows the inversion pulse and at least one readout step of the readout step quantity follows the at least one saturation pulse.
1. A method for acquiring magnetic resonance (MR) image data from a subject, comprising:
providing a control computer of an MR apparatus, with a pulse sequence comprising at least one exposure cycle that comprises an inversion pulse, that inverts a magnetization of nuclear spins in the subject, one or more saturation pulses, that saturate said magnetization, and one or more readout steps that each include excitation of said nuclear spins and wherein, within said exposure cycle, at least one saturation pulse follows the inversion pulse, and at least one readout step follows the at least one saturation pulse, and occurs prior to said inversion pulse; and
from said control computer, operating said MR apparatus according to said pulse sequence, while the subject is situated in said MR apparatus, to acquire MR data from said examination object in order to compile a data file containing said MR data, and making said data file available at an output of said control computer in electronic form.
2. A method as claimed in claim 1 comprising providing said computer with said pulse sequence wherein, within said exposure cycle after said inversion pulse, at least two saturation pulses and at least two readout steps occur without an interposed inversion pulse.
3. A method as claimed in claim 2 comprising providing said control computer with said pulse sequence wherein said at least two saturation pulses and said at least two readout steps occur on an alternating basis, and are coordinated with each other to cause different inversion times.
4. A method as claimed in claim 1 comprising:
detecting a heartbeat of said examination object; and
from said computer, operating said magnetic resonance apparatus by coordinating execution of said pulse sequence with the detected heartbeat to cause, within said exposure cycle, a first of said one or more saturation pulses to occur within a time period of no more than four cardiac cycles after said inversion pulse.
5. A method as claimed in claim 1 comprising:
detecting a heartbeat of said examination object; and
providing said control computer with said pulse sequence comprising a plurality of readout steps, and from said control computer, operating said magnetic resonance apparatus with said plurality of readout steps coordinated to a heartbeat of the examination object, to cause said plurality of readout steps to each take place at consecutive cardiac cycles of a same heart phase of the examination object.
6. A method as claimed in claim 1 comprising providing said control computer with said pulse sequence comprising a plurality of readout steps, and reconstructing a magnetic resonance image from said data file in each of said plurality of readout steps.
7. A method as claimed in claim 6 comprising electronically analyzing said data file to determine a quantitative spatially resolved determination of a T1 relaxation time, and generating a T1 map from the determined T1 relaxation time, for each of the plurality of readout steps.
8. A method as claimed in claim 1 comprising electronically analyzing said data file to determine a quantitative spatially resolved determination of a T1 relaxation time, and generating a T1 map from the determined T1 relaxation time, for at least one of said readout steps.
9. A magnetic resonance (MR) apparatus for acquiring MR data from a subject comprising:
an MR data acquisition unit
a control computer provided with a pulse sequence, said pulse sequence comprising at least one exposure cycle that comprises an inversion pulse, that inverts a magnetization of nuclear spins in the subject, one or more saturation pulses that saturate said magnetization, and one or more readout steps that each include excitation of said nuclear spins and wherein, within said exposure cycle, at least one saturation pulse follows the inversion pulse, and at least one readout step follows the at least one saturation pulse, and occurs prior to said inversion pulse; and
said control computer being configured to operate said MR data acquisition unit while the subject is situated therein, according to said pulse sequence to acquire MR data from said subject in order to compile a data file containing said MR data, and to make said data file available at an output of said control computer in electronic form.
10. A non-transitory, computer-readable data storage medium encoded with programming instructions, said data storage medium being loaded into a control computer of a magnetic resonance MR apparatus in order to acquire MR data from a subject, and said programming instructions causing said control computer to:
obtain a pulse sequence comprising at least one exposure cycle that comprises an inversion pulse that inverts a magnetization of nuclear spins in the subject, one or more saturation pulses that saturate said magnetization, and one or more readout steps that each include excitation of said nuclear spins and wherein, within said exposure cycle, at least one saturation pulse follows the inversion pulse, and at least one readout step follows the at least one saturation pulse, and occurs prior to said inversion pulse; and
operate said MR apparatus, while the subject is situated therein, according to said pulse sequence to acquire MR data from said subject in order to compile a data file containing said MR data, and make said data file available at an output of said control computer in electronic form.