I've been using EFT to clear those for years. One of the easy-peasy things it's helped with. I've always been able to tap the outside corner of either eye on the bone, and say "I seem to have dark stringy things floating in the fluids of my eyes" or how ever you'd describe yours.
Within a minute or so, they've mostly gone with maybe a few vague shadows left, but not usually. You'll want to do it twice for best results. They of course slowly come back after a couple years, but I just tap again and they go away again.
You can give it a try, or not. It's been a totally easy fix for me.