Simply put the following code anywhere on your theme files. If you’re on a comment page, the conditional statement will return true, so any code within brackets will be executed.
$cpage = get_query_var( 'cpage' ); if ( is_singular() && $cpage > 0 ){ // Your code here }
This code works on posts, pages, attachments as well as all custom post_types.
Thanks to Daniel Roch for the cool tip!