| 摘要 |
In magnetic resonance imaging using a measurement sequence of the “free precession of transverse magnetization in the steady state”-type i.e., an SSFP measurement sequence, during the SSFP measurement sequence, the implementation of a preparation sequence takes place to reduce a signal contribution of the transverse magnetization in an outer region surrounding a measurement region in the MR imaging. The implementation of the preparation sequence includes the radiation of a multidimensional, spatially selective RF pulse that acts in a spatially selective manner on the transverse magnetization in the outer region. Saturation of the transverse magnetization and/or dephasing of the transverse magnetization in the outer region can be achieved by the multidimensional, spatially selective RF pulse. |
| 主权项 |
1. A method for acquiring magnetic resonance (MR) data from a subject, comprising:
operating an MR data acquisition unit, with an examination subject situated therein, to implement a “free precession of transverse magnetization in the steady state”-type (SSFP) data acquisition sequence; in said SSFP data acquisition sequence, operating a radio-frequency (RF) radiator to radiate RF pulses that produce a transverse magnetization of nuclear spins in a measurement region of the examination subject and in an outer region of the examination subject that surrounds and adjoins said measurement region, said nuclear spins then emitting an MR signal; also in said SSFP data acquisition sequence, operating said MR data acquisition unit to execute a preparation sequence that reduces a signal contribution, to said MR signal, of nuclear spins having said transverse magnetization in said outer region, by radiating, via said RF radiator, a multidimensional, spatial selective RF pulse that spatially selectively acts on said transverse magnetization of said nuclear spins in said outer region; and operating an RF detector of said MR data acquisition unit, in said SSFP data acquisition sequence, to detect said MR signals and to enter the detected MR signals into an electronic memory, organized as k-space, to produce an electronically accessible data file in said electronic memory. |
