The kind of bilateral visual loss described is seen in Optic neuritis
( can be seen in infections as in Lyme disease).
The treatment of optic neuritis is Steroids. Initially inj.methylprednisolone
250 mg is given 6th hourly for 3 days IV, followed by oral prednisolone 1mg/kg body weight for 1 month. The maintainence may have to be continued in some individuals even upto 6 months to 1 year (decided by regular examination of the eye).
Since he is already on steroids IV, he is getting treatment on the correct lines.He needs to continue with it as advised as steroids will bring down the optic neuritis and bring back some vision.The visual prognosis is better with early start of steroids.
Blood in the back of the eye could mean haemorrhages in the retina which can be seen in optic neuritis( flame shaped). These will regress on their own over a peroid of weeks irrespective of treatment.
As of now he seems to be receiving the right treatment , You can discuss with the treating doctor for the duration of treatment as he would have examined the eye in detail.
Thanks and best wishes
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