Sounds like you have optic neuritis
rather than optic atrophy
The absence of demyelinating lestions in your brain is definately positive, but the presence of a prior neurologic event does indicate that the label of multiple sclerosis
could be applicable... this is really a semantic argument at the point hower.
The absence of plaques in association with this current demyelinating episode is positive. If plaques are present there is an indication for intravenous steroid
treatment to decrease the likelihood of developing multiple schlerosis during the first 2 years after the development of optic neuritis.
The pineal cyst
is far from the visual pathway so is unlikely to have anything to do with your visual loss.