Medical Physics : MRI DP (1 Viewer)

[underthesun]

"Explain that large differences would occur in the relaxation time between tissues containing hydrogen-bound water molecules and tissues containing other molecules".

When I did my research for this DP, i actually went around the net looking for the answers. My DP answer in relaxation is about the nuclei's interactions with other nuclei's to lose energy and relax, but the textbooks never mentioned such.

Anyone can help me? What does Jacaranda tell you?

 

[elizabethy]

i have probs with this dot point tooo....someone pls help!!!!

 

[underthesun]

I just realised jacaranda has no medical physics section..

 

[Shire-miss]

i found that a prob too but ended up finding a site after like an hour that answered the question somewhat... so here's what i found:

Because of the exponential relaxation, the amplitude of the re-radiated Larmor frequency radiation also decreases exponentially. From this, the proton denstiy can be calculated. If a tissue sample contains only water molecules then its proton density will be very high due to the high proportion of hydrogen atoms. Alternatively, tissues being examined that contain other molecules have a much shorter time for relaxation to 63%

hope that makes a bit of sense....