Though I'm not fully convinced this isn't a hoax (Snopes here), an oddity-of-mankind story has been lately circulating the periphery of my info-bubble.
Jewel Shuping claims to have convinced a mental health professional to permanently blind her with drain cleaner to the eyes. "Body Integrity Identity Disorder" drove her to it. She identifies as blind, so she took steps to better match her physical condition with her identity.
I'll spare you links to comments of folks comparing this to FGM or transsexualism, but I'm sure you can well imagine. This sort of story is sui generis, so the details of it can't reliably be used for extrapolation. Still, it's interesting to think about how strong the risk of regret would have to be to propose different interventions. To your humble pedestrian outsider here, this seems more like a case where a responsible therapist would prescribe medication or something.
Then again, I've argued in favor of lifting bans on euthanasia. Who am I to say that this woman's ability to see did not impose on her undue suffering?
Then yet again, it seems pretty trivial to obtain effective prosthetic assistance without having to resort to mutilation. Opaque contact lenses exist, right?