I have had similar symptoms- started with anastrozole and switched to letrozole after 6 months with a month off between medications. I had eye twitching, waves lines (like my eye lashes were in the way of my vision), flashes of light when I blinked and increased floaters. Went straight to the eye doctor and he didn’t see anything alarming- now I find my eyes are dry (like if you wear soft contacts and they are totally dried out in your eye) AND I don’t need my contact anymore, my vision in my right eye is better without the contact. I need to go see the eye dr again but in the interim I had breast reconstruction, dealing with shoulder problems so now it’s time to go back to the eye doctor.
Hope this helps