What kind of meta information should we include while converting from dcm into nii format?

Hi,

I have two sets of MRI images one set in DICOM format and the other set includes two files (*.mhd and *.raw) files for each patient. I have loaded the .dcm files into matlab along with dcm info file. Could some one please help me how can I convert these twp different set (by considering their meta information), how can I convert these two sets into *.nii format with all meta information in both dcm files and (mhd and .raw) files? The reason for conversion is that I am going to do affine registration in another toolbox that only accepts *.nii file format.

I converted a dcm files by NIfTI toolbox, by including

voxel_size=[dinfo.PixelSpacing',dinfo.SliceThickness];

from dicom info file, and I set

datatype = 2; (uint8)
nii=make_nii(IMG,voxel_size,datatype); 
save_nii(nii,strcat(filename,'.nii'));

However, I am wondering whether I am converting correctly or not? Do I need to include other information while creating nii file? Your expert opinion is highly appreciated. Thanks