Just tweaking the read in part.

L4_P1_Q2_view_image

clc; clear all; close all;

res = 512; % # of pixel lines in each dimension
mri_img = zeros(res, res, res);  % initialize image 3D vector
file_names = dir; 
file_idx = 1;

for i = 1:length(file_names)
    name = file_names(i).name;
    
    if findstr('slice', name)
        filename = name;
        f_id = fopen(filename, 'r');
        mri_img(:, :, file_idx) = fread(f_id, [res, res], 'uint16');
        file_idx = file_idx + 1;
        fclose(f_id);
    end
end

figure;
for i = 1:res
    imagesc(mri_img(:, :, i)); colormap(gray);
    pause;
end