Assuming your data has at least 3 dimensions, you only need to index it correctly so as to get a 2D matrix for displaying. For the want of a dataset to demonstrate this, I have used mri. Try running this:
load mri
imshow(D(:,:,1,1)) %transverse plane, first slice.
imshow(imrotate(squeeze(D(:,55,1,:)),90),[]) %sagittal plane, 55th slice.
This is done using SQUEEZE which removes all the singleton dimensions, and IMROTATE which rotates the image appropriately.
