How to compute Reho in 35 and 50 voxels each cluster ?

Submitted by daiqingshi on Tue, 04/14/2015 - 13:28
Dear Pro. Yan
 
I would like to ask a question about the Rest toolbox.
 
Our purpose is to calculate the Reho value in 35 voxels and 50 voxels using the Rest toolbox, rather than in 7, 19 or 27 voxels each cluster.
 
Can we change the number of the voxel by modify Reho.m file? If can, how to do that?
 
Thank you very much.

Forums:

YAN Chao-Gan

Tue, 04/14/2015 - 15:28

Hi,

You need to do is modifying:

block = Ranks_AllVolume(:,i-1:i+1,j-1:j+1,k-1:k+1);

Change the block to fit 35 voxels or 50 voxels.

Best,

Chao-Gan

daiqingshi

Wed, 04/15/2015 - 07:38

Thanks for your replay.

We also want to know can we use the rest to calculate the ReHo value by distance.

For example calculate the ReHo value within 3 mm from the center voxel. 

YAN Chao-Gan

Thu, 04/16/2015 - 13:11

For rmm = 3, you can first convert them into connection criterion:

if voxel size = 2*2*2, 

2*sqrt(2) < 3 < 2*sqrt(3), this equivalent to edge connection (18 neighbors).

You can use this rule to determine the connection criterion.

Best,

Chao-Gan

zhangf123

Fri, 04/17/2015 - 11:30

We got mistakes when calculated the ReHo value after changing the number of voxels to 50.

We changed the “block = Ranks_AllVolume” to fit 50 voxels in the Reho.m, but it didn’t work. The errors are listed.

 “ error(sprintf('There are no appropriate default mask file:\n\tVolume size=79*95*69 ,Voxel size=2*2*2;\n\tVolume size=53*63*46, Voxel size=3*3*3;\n\tVolume size=91*109*91, Voxel size=2*2*2;\n\tVolume size=61*73*61, Voxel size=3*3*3;\n Please set bMask = 0.'));”

How can we solve this problem?

Look forward your reply.

Thanks.

YAN Chao-Gan

Fri, 04/17/2015 - 14:59

This is a mask problem, it's unrelated to the ReHo calculation. Please give a mask which has the same resolution of your functional images.
Best,

Chao-Gan