Now here’s an odd one.
I’ve never been officially diagnosed with optic neuritis, but had occasional mild distortion of colour vision, which could be a symptom (told neuro, was noted down, but no further action or investigation recommended).
Anyway, sometimes, in the dark, I can see almost nothing out of my right eye. I mean that whereas, with my left eye, I can see a bright rectangle where the curtains are - lit by either street lamps or the moon, as the case may be (street lights go off at late o’clock), and make out the dim outline of the room, and of furnishings, with the right eye, I can only see a very faint paler smudge where the window should be, and no detail whatsoever.
It’s quite frightening to realise that you are - for all practical purposes - blind in one eye when it’s dark (I’m a non-driver, so that bit’s OK).
But the weird part about it is: “sometimes”. And I don’t mean for a few days or weeks in a row, as in a relapse. I mean for just half an hour or an hour.
For example, just after lights-out last night, I noticed night vision in my right eye was almost nil. I experimented closing first one eye, then the other.
Left eye: reasonable but dim view of the room. Clear definition of where the window is. Right eye: no visibility of the interior of the room. Pale smudge in the direction of the window.
Eventually dozed off, feeling a bit depressed/frightened (though this has happened before), and telling myself: “Well, if it’s damaged, it’s damaged - it’s not as if you have a problem during the day.”
Yet woke up about an hour later, and found, to my amazement, that although right eye vision was still inferior to the left, there was now much less difference between the two, and each eye could (independently) see the outline of the window, and make out features of the room.
So it’s almost as if the right eye does have night vision, but is very, very slow to switch to it - i.e. takes an hour to notice it’s in the dark,but adapts eventually.
I don’t think ON would toggle on and off like this - especially in as little as an hour - but I stand to be corrected.
Otherwise, is there a name and explanation for this: “eye slow to notice it’s dark” kind of thing?
As I say, it’s not the first time it’s happened. I think I first noticed it pre-diagnosis - so more than five years ago (and I’m not blind yet). But I had the same confusion as now: at one point in the night, the eye couldn’t see, or just barely. But later the same night, it had recovered to almost as good as the “good” eye, so I wondered if I’d dreamt the whole thing.
Can ON be so variable over such a short timescale?
Is it some kind of fatigue, and sleeping for an hour fixes it?