Remember when you was a child and your parents tell you not to look at the sun or you'd get blind? The same goes for monitors because monitors are light emitting, not light reflective.
The less light, the best for the eye. Black and grey, grey + light grey are what it is needed. High contrast is not good, too much light. I guess it may be for those having macula degeneration or something like that. Just, try less brightness.
I just use Black Mate + Blue Submarine with Ubuntu-mono-light icons (plus some others specifically set on some launchers etc. borrowed from others icon themes) and this Shogo Maikishima Wallpaper. Also, install Workrave. GREAT SOFTWARE. Use Ctrl+ + for zoom. Do make use of the reader of Firefox and read this fresh thread and install the add-on I talk about there.
Also, you may have been diagnosed for eg. astigmatism but you wasn't for something else, like CVS. Read the following stuff and tell your (new) ophthalmologist about this stuff (if he/she doesn't care, go look for another).
and a rare news here:
For those who think you are safe because you see now, you are not. In 10 or 20 years the effects of the brightness and the white background on your retina will strike you. Are you needing more and more white or brightness over the time? That's the first symptom. Moreover, the distance for reading is something that no one takes into account...
You have been warned 
