Question

8. At what point (timing in the sequence) is the phase encoding gradient turned on?

Answer 1

(Gf) The phase encoding gradient is a magnetic field gradient that allows the encoding of the spatial signal location along a second dimension by different spin phases. The phase encoding gradient is applied after slice selection and excitation (before the frequency encoding gradient), orthogonally to the other two gradients. The spatial resolution is directly related to the number of phase encoding steps (gradients).

A phase encoding gradient is applied between the 90° and 180° pulses. Means it starts from at T/4 to T/2