Is it permissible to use a tattoo to cover a birth defect in the chest that is impossible to remove?

Seeking medical treatment is permissible, for Allah has not sent down a disease but that He has also sent down its cure. You are allowed to treat this defect and others. However, treatment with tattooing is not permissible, because it is among the forbidden acts and major sins, and because the tattooed area becomes impure. The jurists mandate purifying it, even if by surgery.