MRI - Localising signals (1 Viewer)

[tazzyboys]

Ok, I know theres two processes involved in localising where the radio pulse originates from:

1. Using gradient B field to change the lamor frequency along the length of the body - this differentiates the frequency at which the radio pulses return

2. Something about PHASES of the NUCLEI??

No idea what number 2 is about, can anyone clear this up?

Thanks.

 

[alez]

as in the t1, t2 and proton density?
not sure what you're asking...

 

[tazzyboys]

Yeah im quite sure it's associated with relaxation time
Basically my question is how the computer can differentiate the different locations of nuclei (protons) in the body. For eg if they all use the same ext. B field the lamor frequency will be the same throughout the body