Hi, I get something similar with my eyes actually. If I look at lines- particularly bold black lines I see a set of clear lines running through them the opposite way that almost makes them wobble a bit. I always assumed it was part of astigmatism because people complain about stripes and things (as do I)...obviously I cannot tell you for sure but lines do seem to be a problem for astigmatism.
I ended up booking a topography at the opticians last night. Have no idea when it will be as they haven't responded yet, I feel physically ill thinking about it as the possibility of eye stuff truly terrifies me but I know that if everything is all fine then I will never have to worry about this again, and since my allergic eye rubbing between around 19-22 this has always been a concern of mine for a while now, an even worse concern when I developed astigmatism last year... so it would feel like a massive weight off the shoulders!