[Cited from: JOURNAL OF COSMETIC AND LASER THERAPY, Authors: Debora Aparecida Oliveira Modena, etc.]

 Discussion

Post-inflammatory hyperpigmentation and hypopigmentation may also occur in some cases, particularly when the inks present blends with minerals such as zinc, titanium dioxide, and others. When the energy comes into contact with these pigments, a chemical modification of their composition occurs, and thus they may react with the darkening of the ink or the surrounding tissue or the hypopigmentation of the treated region.

Concerning pain, when comparing to the application of the Nd:YAG Q-S (www.wisoptic.com) caused less discomfort during the procedure. Pain is a common adverse effect, with short duration after the tattoo removal treatment; however, topical anesthetics or cooling mechanisms may be used to minimize this effect. Out of all the studies selected, five used local anesthetics to lessen pain or discomfort.

Regarding methodological quality, the findings demonstrate that there were only a few randomized studies, and out of the six studies included, all of them presented different methodological types such as types of randomization methodology, blinding of patients or evaluators, and evaluation methods. The Downs and Black scale was used, which is adequate to evaluate randomized studies, and provides a score for the quality of the study and an external validity profile of the research to comprehend the adequacy of the selected studies.

The articles were classified as good and/or regular with scores from 17 to 22. The ain points which presented deficiency among the studies included in this review are the blinding of patients, considering that is an extremely important methodological point to avoid eventual bias and is, nevertheless, seldom employed due to the nature of the intervention; and the identification of the parameters, among others. This information, which was not mentioned accurately in the studies more difficult in terms of the recommendation of the therapy and qualification of their level of evidence.

Considering the level of evidence of the Nd:YAG laser therapy in the removal of black and color tattoos, according to the studies included in this review, we can infer that the therapy presents a level of evidence 2 c, based on the recommendation of the Modified Guidelines by Oxford Center for Evidence-based Medicine. That is, there is a need for further controlled studies with better methodological quality that assure the safety and efficacy of the Nd:YAG laser therapy with this objective. However, short-term and long-term tattoo removal treatments are indicated with precaution and moderate strength of recommendation.

Conclusions

From the results of this review, we conclude that the Q-swithced 1064 nm/532 nm Nd:YAG laser presents safe and beneficial effects and is promising in the treatment of black and color tattoo removal with minimal adverse effects in the short and long term, and is regarded as a level of evidence 2 c. Nevertheless, there is a need for further scientific studies with better methodological quality since all the articles included presented methodological limitations and a scarcity of data, which hinders a standardization of the Q-switched 1064 nm/532 nm Nd:YAG laser therapy in the treatment of tattoo removal.