I can't see some colors in my crosshair

Do you guys have this problem too? I have some problems seeing due to some conditions (myopia, astigmatism, keratoconus and diplopia). I use contact lenses and cant see my crosshair in some sand maps like mirage or dust2 because of the colors, like green, yellow, cyan (the most common). Even the pink and red ones. I do accept ideas if you have any.