Hi everyone,
I have a question with respect to normalization in SPM. I thought that when we normalise to MNI space, the nii resultant had the same dimension for all studies of patients independently of dimensions of the original image.
For example,
I have a T1 of subject 1 with dimensions 256x256x186 and [0.94 0.94 1.00 ] size of voxels , we realign the image with the images SWAN, first we choose T1 and second SWAN and we choose the option "Register to first" and the resultant images with prefix r, T1 and SWAN have the dimensions 256x256x186 and [0.94 0.94 1.00 ]. After we normalise with option "estimate and write" we choose in "image to align" r_t1.nii image and we select r_swan.nii in "Images to write". We change the "voxels size" to [0.94 0.94 1.00 ], the rest of values by default. The resultant image wr_swan.nii have a dimensions 167x201x156 with size of voxels [0.94 0.94 1.00 ].
And now the T1 of the subject 2 have the following dimensiones 512x512x248 and [0.47 0.47 0.5] size of voxels and following the same procedure that with the subject 1, the wr_swan.nii resultant has a dimensions of 333x402x156 and [0.47 0.47 1.00] size of voxels.
Is this correct and normal? I need to compare the images SWAN of the differents patients.
I would have to put the same size of voxels for all patients? For example the default values [2 2 2] ?
Is normal that when we normalise to MNI space we have images with different dimensions if the original images has different dimensions or size of voxels?

I'm using PET & VBM in SPM 12.
Thanks to everyone in advance
Best regards
Laura