| 摘要 |
The present invention relates to a MRI device (1) comprising: means (2) for applying a main magnetic field B0 on an axis Z over a sample zone (8); means (3) for emitting a magnetic field gradient and means (4) for emitting a radiofrequency pulse, and control means (5) arranged so as to control the means for emitting a magnetic field gradient and the means for emitting a radiofrequency pulse. The control means are programmed to carry out at least one set of repeated applications, on the sample zone, of a sequence comprising: a radiofrequency pulse possibly of variable amplitude and/or phase at each repetition; and after the radio frequency pulse, a spatial gradient of the component along the Z axis of the magnetic field. The control means are programmed so that, in the course of repeated applications of the radiofrequency pulse and of the magnetic field spatial gradient of the sequence of one and the same set: the radio frequency pulse follows, between its various repeated applications, a periodic series (preferably non-constant) for its amplitude and for a series un +l =vn +l -vn ; and each repeated application of the spatial gradient of magnetic field of the sequence a, according to a so-called coding spatial direction, a non zero timing integral equal to A and identical for each application of gradient of this set. The invention also relates to the method implemented by this device. |
