Multi-echo sequence

Submitted by GLM on Thu, 10/02/2014 - 23:55


Dear colleagues,

 I have a question regarding a “new” resting state sequence which we are using in our lab.  

It is multi-echo EPI (3 different TE). The question is how should I analyze these data? Should I keep separate the 3 image for volume or should I average them? And which kind of average should I apply? Consider that my intention is to perform correlation and ICA analysis. Any suggestion from who has experience which multi-echo sequence will be highly appreciated.

 

Best wishes,

Gianluca.

Submitted by zewang on Wed, 10/22/2014 - 09:04

 Hi,  multi-echoes will have different contrast and signal intensities due to the T2 and T2* decay, so you cannot combine them for either FC or ALFF or ReHo etc.  I would suggest divide them into 3 different image series, one for each echo. Because only one TE is in the range of the optimal value, you may not get useful information from all echoes.  The image distortion from later echo will be extremely large.
Wish this could be helpful

Ze Wang