User blog comment:Miskos3/Fairy Tail Episode 259: Tartaros arc: 00:00, Review/@comment-24277053-20151114042416/@comment-4933386-20151114050009

I think the fake eye saved her during those times is because those are the times when her sense of sight was not removed. Because if that sense (sensory photoreceptors) is removed, or shut off, even if you have billions of artificial eyes in your body, you still can't see without those receptors sending the messages to your brain.