Question

if a fast spin echo sequence has a parameter at 256 x 224, 3 NEX w/ a FOV of 24. How many times will the PHASE encoding steps have to be filled inorder to correctly produce a quality FSE?

Answer 1

The phase encoding steps for a fast spin echo sequence with parameters 256 x 224, 3 NEX, and a FOV of 24 will have to be filled 672 times (224 steps times 3 NEX) to produce a quality FSE image.

Step-by-step explanation:

If a fast spin echo sequence has a parameter of 256 x 224 with 3 NEX and a FOV of 24, you are being asked how many times the phase encoding steps will need to be filled to produce a quality FSE image. The first number in the parameter (256) represents the frequency encoding steps (also called readout steps), and the second number (224) represents the phase encoding steps. The NEX, or number of excitations, further multiplies the number of times each phase encoding step is sampled.

In this case, since there are 224 phase encoding steps and the sequence will be done with 3 NEX, each phase encoding step will be repeated 3 times. Therefore, the total number of times the phase encoding steps must be filled to complete the image acquisition is 224 (phase encoding steps) multiplied by 3 (NEX), which equals 672 times.