SE Последовательность эхо-импульсов жесткого импульса

SE Последовательность эхо-импульсов жесткого импульса

Введение

If we put another 180-degree pulse after 90-degree pulse, it will become the spin echo sequence which is also
called hard pulse echo sequence.

Pulse sequence parameter

SE sequence is shown in figure 1.

инжир 1 SE sequence

RFD: The sampling time of the first sampling point is controlled by the delay time of the 90° pulse, in ms;

П1: hard pulse 90° pulse width, unit us;

П2: hard pulse 180° pulse width, unit us;

TE: echo time, in ms, the time interval between the 180° pulse and the adjacent 180° pulse;

TW: repeat sampling waiting time, то есть, the time between the end of the previous sampling and the start of the
next sampling, in ms;

ACQ: The total time of signal acquisition, in ms