After the initial period of nerve atrophy where the nerves became progressively more pale over a period of about a year, they had remained stable. Recently a teacher at his school was concerned that his vision was again deteriorating and they did another functional vision assessment. According to the tests he is now color blind - although I'm not entirely sure that is accurate. Any pastel is white, if they are a little darker, then they are grey.
Dark green is brown.
Dark blue and black appear to be different than dark green and brown. Orange, red and pink are the same. It very well could be that he has just memorized the various shades of grey associated with the colors that he can still recognize. He is 8 years old but unwilling to discuss what he can and cannot see. My hope is that this is common with progressive optic nerve atrophy, but my concern is that it is a sign of other eye problems such as retinitis pigmentosa - which is not uncommon in mitochondrial disorders.