How can I display multiple DICOM images on Matlab?

I am trying to display multiple DICOM images at once. I have the dicom images in a folder called 'patient1scans'. It contains 133 images. I eventually want to try to display 10-20 images per page at a time, but I want to first figure out how to display all of them. I have tried using the code below but it keeps saying "undefined functions or variable 'nume1'. and error in 'for i = 1: nume1(files)'. I'm not sure if using subplot would be the best thing to do, or is there a better way? Please help. Thank you in advance.

files = dir(fullfile(pwd,'patient1scans\*.dcm'));
for i = 1: nume1(files)
  [X, map] = dicomread(fullfile(pwd,'patient1scans',files(i).name));
  if ~isempty(map)
      subplot(2,2,i);
      subimage(X,map);
  else
      subplot(2,2,i);
      imshow(X,[]);
  end
end

[Karl Largo]

I was able to get the code above to work. If I change the numbers in the subplot function, I can change how many images are gonna be displayed. However, when I try to change it to subplot(12,12,i) , it takes a really long time for it to run and display the images ( i changed it to 12 because 12 x 12 = 144, and Im trying to display 133 images.). Is there a way to display 20 images at once per page and then have some kind of next page function to show the next 20 images? thank you in advance.