Improperly sized lenses can cause corneal abrasions, corneal ulcers and potentially blinding painful bacterial infections like keratitis. Treating these injuries can require eye surgery, like a corneal transplant. Packaging that claims ‘one size fits all’ or ‘no need to see an eye doctor’ is wrong. How to Make an Assassin’s Creed Costume. Costume, cosplay or theatrical contact lenses also might let less oxygen through to the eye, because the paints and pigments used to add color make the lenses thicker and less breathable.