When you have fuchs' and your eye dr does the standard 
eye chart test the numbers you get may not give a true 
reading of what your vision REALLY is. Many people with
fuchs' may get a really GOOD eye exam number, when, 
in REAL LIFE conditions they can't see much of
anything! Why is that?  Because most eye drs. 
do that test in an unreal situation:  with the 
lights dimmed or off.  Fuchs' Dystrophy is a cornea 
problem, which is what assimilates the light going 
into our eyes.  Since there's not much (if any) 
light to bother you the reading will probably be 
better that your actual real-life vision is.

What may perhaps be a BETTER indication of your 
vision is to do the same test, but ask the dr to 
shine a light TOWARDS you while standing by your side.  
THEN look at the eye chart and see what you can see.  
Usually, the worse your fuchs' is, the more likely 
it is that you won't see anything at all then!!! 
This test is called the "glare test".  An even better
why of performing the "glare test" would be to be in
a dark room (like a regular eye test), but have the
person with a flashlight in FRONT of you (NOT 
standing right between you and what you're trying to
see, though; make sure there is a direct line of sight
to the object) and shine the light in your eyes.