(RxWiki News) Put some careful thought into what's inked on your body. Even though tattoos can be removed, some are zapped away better than others.
Two new studies looked at how well tattoos could be removed using a couple different kinds of lasers and what characteristics made it easier to remove those tattoos.
"Talk to a dermatologist about tattoo removal."
One of the studies involved the Q-switched laser, a standard treatment for removing tattoos which is commercially available.
The second instrument was the newer picosecond 755-nm alexandrite laser, which pulses time-wise about 100 times less than the QS laser.
The first study led by Pier Luca Bencini, MD, included 352 patients averaging 30-years-old who were treated with one of two kinds of Q-switched lasers depending on their tattoo colors.
The tattoos ranged in age from six months to 30-years-old and were between half a centimeter to 980 square centimeters large.
Almost 93 percent of the tattoos were on the trunk of the body or limbs. The rest were on the face and neck.
Patients were photographed at the start of their first removal session and four weeks after the last laser treatment.
The patients had between two and 18 laser sessions scheduled at six-week intervals or longer. Their goal was to remove the tattoo with no adverse effects.
At the end of all the removal sessions, two independent observers looked at the photographs and measured how well the tattoos were removed.
The observers did not know how many treatments each patient received.
In the second study, led by Nazanin Saedi, MD, a physician at SkinCare Physicians in Massachusetts, researchers looked at how well a picosecond 755-nm alexandrite laser removed tattoos from 12 participants, ranging 19- to 76-years-old.
"Picosecond lasers are an emerging technology that has the potential to optimize the treatment of tattoos," the authors said in their report.
The patients were photographed at the start of their tattoo removal and after their last treatment. Their treatments were also about six weeks apart.
The lasers pass over a 2.5 to 3.5 mm area skin using 150 to 200 mL of energy and pulse 500 to 900 picoseconds.
The area treated depends on the patient's skin type and how well the skin whitened during the first test.
The patients rated their pain as a 4.5 out of a 10-point scale. Only two of the 15 patients received a topical anesthesia and reported a pain score of 1 out of 3.
In the first study, researchers found that a little more than 47 percent of patients successfully removed their tattoo with the QS laser after 10 sessions. By 15 sessions, that rate increased to almost 75 percent.
They also found that more time between treatments might also improve tattoo removal.
The tattoos of all 12 patients who were treated with the picosecond laser were at least 75 percent clear after about four treatments.
Tattoo removal was not as successful among those who have:
- colors other than black or red, or highly dense patches of color
- tattoos larger than 30 cm wide
- tattoos located on the feet or legs older than 3 years
- went eight weeks or less between treatments, and
- developed a darker patch on their tattoo
Smokers have an almost 70 percent lower chance in successfully removing their tattoos compared with non-smokers, the researchers found.
And after 10 treatments, the chance of successfully removing a tattoo with colors other than black or red decreases by almost 80 percent.
Although researchers in the first study did not take patients' satisfaction into consideration, the second study had patients rate how happy they were on a four-point scale.
The first study noted that only tattoos done professionally were included in their study. Those tattoos from amateur artists or caused by traumatic experiences were excluded.
The researchers using the QS laser also did not look at the areas of the tattoo before and after laser treatment.
To the best of their knowledge, researchers said in their report, this is the first study of its kind to analyze the factors for effectively removing tattoos.
"One advantage of our study is that it examined several variables simultaneously, providing a more complete profile of factors that may affect clinical response after reciprocal adjustment," the authors said in their report.
Funding information was not available for the first study, but the second was supported in part by Cynosure.
Although authors from the second study serve as consultants to Cynosure, the authors do not declare any conflicts of interest.
The studies were published online September 17 in the Archives of Dermatology.