Successful removal by ruby laser of darkened ink after ruby laser treatment of mismatched tattoos for acne scars.

Cosmetic tattoos are becoming increasingly popular. Elimination of cosmetic tattoos is sought because of misplacement or migration of tattoo pigment, allergic reactions to the various pigments or dissatisfaction of the customer for various reasons. Removal of unwanted pigment is a domain of laser surgery using various Q-switched laser systems, such as the ruby, alexandrite, pulsed dye and Nd:YAG lasers. Dark colours are easily removed by these lasers, whereas red, pink and skin-toned pigment may turn black if exposed to Q-switched laser light. This ink-blackening occurs because Q-switched lasers heat up the pigments, which consist of ferric oxide, and reduce them into ferrous oxide, which is black. Laser-induced black ink is not always readily removed. A successful ruby laser-removal of laser-induced blackened cosmetic tattoos for acne scar camouflage is reported. The advantageous outcome in this case contrasts with other published cases where laser-darkened pigment had to be removed by other measures, or was permanent. Test site treatment can limit the problem to some degree but, in addition to test-treating, some kind of 'tattoo identification card' could help to prevent problems in this field and allow 'in vitro' test treatment.