H's brush is an inconsistent and unreliable entopic phenomena and of no use in diagnosing ARMD which is made by exam of the eye by various instruments and macular OCT. I would just see an ophthalmologist Eye MD tell her/him of your concerns and worries. Also read the entire section on entopic phenomena on Wikipedia.
My findings,
I can see it now on tv and monitors, tilting the head or just moving it towards the image makes me see it, if I move the head it moves like the blades of a fan.
If I see the monitor without glasses -myopia- and put them on, I see it.
I see it for the first time when I drank water while watching the monitor, now the brain is not filtering it I guess.
And this is what I would like to find the cause as it may help to understand it better, I dont see if I use photocromatic lens.
They say the retina is all right so I have yet to do neuro tests, is that Im in venezuela and things are a bit hard here to get proper examination.