Not sure whether this is FAct or not, but my optician said that he has never come across any diabetic, who has been diabetic for a number of years, who doesn't have minor changes to the back of their eyes. His view was this was side effect of diabetes, but, if god control was kept, the only person who would ever be aware of it would be him, and you would not have any problems with it all.
This conversation did happen 15 years ago though...so whether thsi is still true, with better BG ccontrol I do not know.