A man in Toronto has been the first to get an eyeball tattoo. Basically, he has turned the whites of his eyes blue. Corneal tattooing is usually used for patients that have had trauma to their eye, not for this, which is called body modification.
It took 40 injections of blue ink in order to complete this procedure. Pigment was injected under the top layer of the eye using a syringe. The syringe injected the ink into the eye. At first they had tried a traditional needle with ink on it, but when the ink didn't hold, they switched to the syringe.
The man has reported that all is well so far, but it feels like he has something in his eye.