We've had 3 cases in the past week of contact lens patients coming in with corneal ulcers. Ulcers are bacteria that can eat away at the cornea (the clear layer of tissue over your eyes). Even with treatment, ulcers tend to leave scars. This patient continuously sleeps in her lenses even though Dr Sao NEVER recommends it; even with lenses that are approved for overnight wear. The ulcer happened to be in the center of her line of sight so she now has reduced vision.
We don't take sight for granted. Like earth, we do whats best to preserve what we have.