the best thing for hope is hearing other people who suffered optic neuritis and came good again.
i remember last year during my time, i met a young man who was next to me in the day treatment unit and receiving the same IV steriods as i was for optic neuritis. for me who'd never heard of it, or know if i would see again, it was so good to talk to him, as he'd suffered them many times over and always regained his sight.
you will regain sight and your body is fighting as hard as it can, the port sounds like a great idea, maybe some easier and direct access will have a better effect for you. i know it took me over 2 weeks to notice any improvement in my sight, so hang in there, it will come back!!!